“Explore” set some business media hearts a-twitter (for example…) upon release, with stories of how innovative this site is, but I’m sorry, it’s not good enough. “Explore” is neither a new idea nor the best possible execution of that idea.

Travelocity had “Dream Maps” years ago, which mapped fares from a given city. You clicked on the fare on the map, and you got a detailed list of the fares, the airlines, the fare codes (!), and the rules/dates applicable. You could click on a fare and a calendar with eligible dates popped up. You could choose dates and search for availability on the spot. I miss this.

One major reason I miss Travelocity’s Dream Maps is because they listed all the publicly available fares that were loaded into Sabre. Sure, you had to click through a number of fares before finding something that met your dates, but they were bookable. That’s not what Kayak is providing. You’re not seeing all possible fares. Instead, Kayak’s “Explore” pulls fares from a much more limited pool. From the site itself (emphasis added):

Fares displayed are for round-trip economy class travel found by Kayak users in the last 48 hours. Fares include all taxes and fees but may not include baggage fees charged by carriers. Seats are limited and may not be available on all flights or days. Fares are subject to change and may not be available on all flights or dates.

A rolling 48 hour window of search results is problematic in a number of ways. Not only are fares rapidly outdated, and thus useless in a search, but by limiting your results only to those cities where someone else has found a fare in the past 48 hours, you’re only getting a small number of actual fares. You’re essentially relying on others doing the searches for you. And those fares are pulled for specific dates, not a range of dates. Not necessarily your dates.

The fact that the range of results — based on other people’s searches in the last two days — is likely to be limited is especially problematic if you’re searching from small airports. New York fares might be pretty reliable, but how about Walla Walla, Washington fares?

Other sites have taken a stab at this, too. FareCompare currently comes closest. But I’ve had trouble actually booking some of the fares that come up. Mobissimo lets you search by regional destinations, too. And again, some of those fares aren’t bookable.

Bottom line: I like the idea of Kayak Explore. It’s a great concept. But someone (else?) can and should make it better. I know it’s a moving target, and a big set of data to sift through, but it was done once. Let’s map the complete range of bookable fares — again — to truly empower the consumer.

Related:
- Flexible-date search alternatives for international destinations
- Reader mail: I don’t care where I go, it just has to be cheap

Upgraded: Advice for worst-case aviation scenarios
No one wants to think about what they would have to do in the case of an inflight accident. But if you were to survive such an event, make sure you’ve read this guide to surviving a 35,000-foot fall.

Downgraded: Machu Picchu
Sad news: The train line that provides access to the ancient Incan city of Machu Picchu in Peru has been washed away, destroyed by recent flooding. This not only has devastating consequences for tourism in the immediate vicinity of the ruins, but for Peru as a whole:

Whether the fault of a mafia-like Cusco tourist industry, simple laziness by foreign and local tourism companies who slap an image of Machu Picchu on advertising and say “that’s Peru”, or the ignorance of cash-rich tourists happy to hand over money and be taken to where they are told – the result is the same. A Peru without Machu Picchu, despite there being dozens of equivalents across the country, is a country with a tourism industry in trouble.

See here for more amazing photos and videos of the destruction. Also here, for a sense of the breadth of the humanitarian disaster in Cusco.

Upgraded: Kayak’s hotel deals
Kayak, the leading fare aggregator, is following the online travel agency trend and pushing harder into the hotel space. Not only are they offering metasearch capabilities, which they have long done, but they’re now branching out and offering “private sale” rates. Though they’ll be technically sold directly by the hotel, it’s direct competition with the online travel agencies.

Upgraded: Hotel booking advertisements
Upgraded: Japanese business-cats
I don’t speak Japanese, but I suspect that this is an ad for a travel booking engine targeted at business travelers. Or at cats who travel on business. (Anyone who speaks or reads Japanese is invited to help with the translation. What’s on the business card??) The awesomeness of these 13 seconds cannot be overstated.

Upgraded, but not quite enough: Kayak’s search engine
A month ago, I reviewed the airfare aggregators or metasearch sites. I gave TripAdvisor’s new engine the win, largely because of its ability to estimate ancillary fees like luggage fees. Now, Kayak is adding a baggage fee estimator as well, as pictured below. But it’s not quite to the level of TripAdvisor’s engine, which takes into account factors like elite status, and allows for a more granular approach to fees than simply asking about number of bags.

Downgraded: Nicknames and Abbreviations
TSA is rolling out the first phase of its “Secure Flight” policy, which means your plane tickets will have to match your identification more precisely than in the past. “During this phase of the Secure Flight program, passengers are encouraged to book their reservations using their name as it appears on the government-issued ID they will use while traveling.” And that means that, at some point (though not today), you won’t be able to use a middle initial on your ticket if your ID uses your full middle name. Which will piss off thousands of passengers while doing absolutely nothing for security. Asinine.

Downgraded: Hotel searches for Columbus, Georgia
If you’re staying in the town of Columbus, Georgia, you won’t find much in the way of hotels if you search the major online travel agencies. Why the boycott? Expedia was ordered to pay occupancy taxes to the city on the basis of the displayed room rate (the one paid by customers booking on the site). Previously, they had been paying the occupancy tax on the basis of the wholesale rates which they had negotiated with the hotel. So, now the major sites are simply not listing hotels in Columbus, GA at all. I’m no lawyer, but I can see the agencies’ point here: It makes sense to me that local taxes should be based on the rate paid locally — in this case, at the wholesale rate. I’m sure Columbus hoteliers are thrilled…

Downgraded: InterContinental brands
InterContinental is downgrading their properties’ service requirements. Gary Leff has the rundown, which, depending on the brand in question, includes delaying the purchase of new beds, cutting restaurant hours, cotton towels, and overnight front desk service.

For starters, there are sites which have folded, some new competitors, and sites that changed their model significantly. At the same time, there has been pushback from airlines and suppliers, some of which have resisted the aggregator model. (The lawsuits between American Airlines and Kayak, which initially resulted in American Airlines no longer being listed in Kayak results, was perhaps the most prominent case of pushback. Since October 2008, aa.com results are back in the results. More on that below.)

The result: The golden ring of a truly complete search, covering all the options and all the providers, is still a ways away. No single site actually finds every flight option, every fare, or every seller.

But that doesn’t mean that there aren’t differences between the aggregators. It’s time to disaggregate the aggregators again.

This year, each site was put through multiple tests. Four kinds of itinerary were tested: A large-city to medium-city domestic US flight with multiple carriers offering direct service; a medium-city to small-city domestic US flight with at least one change of plane required; an international flight with a US origin; and international flights (from Paris to Dubai, and Manchester to Madrid) to test how sites do for non-US flights. For each of these flights, I tested a short-term booking (7 days advance purchase) and a longer-term booking (30 days advance purchase).

This time, I compared Kayak, Sidestep, Mobissimo, TripAdvisor Flights, Momondo, Skyscanner, WeGo (formerly Bezurk), Trax, Farecast, Fly.com, and Dohop. Sites which were on the list last time but either folded or stopped doing metasearch include FareChase (bought by Yahoo, then abandoned in March 2009), PriceGrabber, and Qixo.

So which aggregator came out on top in 2009? Here’s the summary, with site-by-site reviews thereafter…

• Overall best bet: TripAdvisor Flights. Low fares, good features, a solid performer overall. It took them a while to join the game, but it’s a strong product with a small but important edge over its closest competitor, Kayak.
• Lowest price, domestic: If you’re searching for domestic US airfare, most of the aggregators did pretty well, but the lowest fares were consistently on TripAdvisor Flights, Mobissimo, or Momondo (Kayak and Sidestep would have been included in this list, but they often offered the lowest flights at the same base fares, but typically directed you to Orbitz, instead of to the airline or to a no-fee site like Priceline, to buy the ticket. Orbitz still charges a booking fee as of this writing, so single-airline itineraries can typically be purchased for less elsewhere.)
• Lowest price, international from US: If you’re searching for international flights starting in the US, try Kayak and Trax.
• Lowest price, international, ex-US: If you’re search for international flights that don’t originate or end in the United States, Mobissimo and Momondo performed best.
• Class conscious: If you’re looking for a deal on premium cabin fares, fly.com is your site.
• Sorting features: If you want control over options, and like to tweak and limit your results, Kayak gives you the most power.
• Real total cost: TripAdvisor Flights lets you estimate what your actual costs will be, including luggage checking fees, headphone charges, etc.
• Avoid: WeGo, which offered impressively-low search results, but none were actually bookable. Also avoid Dohop, whose prices were consistently higher than their competitors.

Individual site reviews

TripAdvisor Flights
Although a clone of its competitors in many respects, TripAdvisor’s new aggregator offers one big difference: The site offers an analysis of how much the flight will actually cost you, once you figure in the baggage fees, the headphone fees, etc. It even considers what your elite status is. That’s a great feature. Second, and more disappointingly, the site (unsurprisingly) favors its sister sites Expedia and Hotwire in its results. But those sites add no booking fee right now, so no big whoop. The site combines the best sorting features of Kayak with the added value of fee analysis. TripAdvisor takes it by a nose.

Kayak
Kayak is the largest of the metasearch sites, and it offers solid results. But it didn’t consistently offer the cheapest fare, because the universe of sites it searches is sometimes limited by agreements with individual partners. (American Airlines, for example, won’t allow results from its website to be shown alongside AA flights sold through Orbitz.) Orbitz puts demands on its partners, too, and subsequently, Kayak is heavily Orbitz-centric, with no representation of Expedia, Travelocity, or Priceline. Actual fare availability was good when I clicked through to sellers’ sites. Kayak’s sorting features are still the best (so good that they’re copied wholesale by TripAdvisor), with the ability to narrow search results by time, airline, or aircraft type (e.g., no props or RJs), to name a few. The site has recently added “flight quality warnings,” such as on-time percentages and tight-connection alerts, but those aren’t a big deal.

Sidestep
Kayak bought Sidestep a few years ago, but continues to operate the site as a standalone entity. Frankly, I don’t see why. The results are identical, the search tools are nearly the same, and there’s nothing to recommend this site over its parent. Everything stated above is true here as well, but why bother?

Farecast
Farecast, now owned by Microsoft, is most famous for their fare prediction engine, which suggests whether ticket prices for your route will drop in the future. The predictions are pretty accurate, though they don’t account for times of day, routing, or airline, if you have preferences on those matters. (And you should.) Farecast also offers up an aggregator, albeit a fairly minimalist one with few options and a favoritism for Orbitz results. Come here for the fare predictions, but for live fare comparisons, you’re better off elsewhere.

Mobissimo
Mobissimo claims to search more sites than anyone else, but not necessarily for a domestic US search. They have good coverage of Asian and European airlines, but their controls and filters are less than others’. Decent results, but I preferred others’ display of information.

Fly.com
From the folks who brought you TravelZoo, Fly.com offers one gimmick that’s worth noticing: First- and business class fare comparison. That’s it. Otherwise, it’s a clone of other sites. If you’re not looking for premium cabin seats, skip it.

WeGo (formerly Bezurk)
Big on teasers, low on success. WeGo touts some amazing fares, but good luck buying them. They also don’t list the lowest flight first: They show a sponsored link at the top. Bad, bad, bad.
Update April 9, 2009: WeGo has eliminated the sponsored results feature.

Skyscanner
Britain’s SkyScanner offers decent results for UK-based searches, but it’s not as helpful to others. For US and non-UK searches, SkyScanner searches returned far higher fares than the average.

Momondo
This Danish site is quite good at ferreting out obscure sellers of travel, especially for intra-European itineraries. But be aware that you’ll often get results from suppliers in countries outside the destination or origin. Flying Chicago to Baltimore? Your ticket could be sold by a British company (which could mean a 3% credit card surcharge).

Trax
Update December 2009: Trax has retrenched, and is no longer touting their fare comparison as their primary product. Their homepage shows a disclaimer as of December 7, 2009. But their search engine is still up and running if you dig for it… This is odd, to say the least.
Trax.com offers a Kayak-lite search that works well for domestic US itineraries. They include Priceline and Cheapoair, which others don’t, but the results weren’t significantly better.

Two other sites of note:
1. An aggregator you can’t use for booking, but which is great for research, remains ITA Software. Their engine powers Orbitz, and backs up Kayak and TripAdvisor results. They’re a great resource. (Click “log in as a guest” to use the search without registering.)

2. No discussion of fare search would be complete without a mention of FareCompare. The site’s alerts give you a heads-up on future sales by notifying you when fares drop, before they go on sale. They offer fare search, too, which is powered by Kayak.

So… what’s your experience with fare aggregators? Hit the comments to share your stories.

TechCrunch also reports, citing “the CEO of a competing travel site” as a source, that American is “considering doing the same with Orbitz. If it does so, other airlines such as Continental and Northwest may follow suit.”

For starters, this stinks for consumers, because it’s making comparison shopping harder. Already we’re stuck comparing apples to oranges, thanks to the variation between the airlines’ myriad fees. But in the long run, I’m betting that pulling out of comparison sites will stink for the airline, too, and we’ll see this decision reversed.

The comparison with Southwest will inevitably arise. Sure, Southwest doesn’t show up in comparison sites, but Southwest customers have been “trained” for years now to skip the search engines and go straight to the airline. American doesn’t have that kind of culture built up, and it’s unlikely to go all-in toward creating such a culture at this point. Just pulling out of Kayak won’t do the trick. And worse, it’s a real pain in the butt to waste time looking all over the internet for the lowest fare. I have always disliked that about Southwest, but hey, it’s working for them. Still, Southwest is the exception — not everyone can pull off selling tickets solely on their their own. Even JetBlue caved in and started publishing fares on other sites.

American Airlines has played these games before. They once yanked first-class fares from Expedia, but came back three weeks later.

This sort of thing goes both ways, too. Notably, online travel agencies don’t claim to cover ALL the options. Orbitz, for example, limits customers’ choices in its rental car search to those companies that pay to be included.

I’m betting that American’s pullout is a bargaining strategy. They hate to pay any referral fees to sites that drive them customers, but they don’t want to lose those customers entirely. Their real goal: to negotiate a smaller revenue split with Kayak and/or Orbitz.

If I’m right, then American’s fares will be back online for comparison shopping within a month or so. If I’m wrong, then we will likely see other airlines do the same, and the business model of Kayak and its competitors is at risk. It’s not just venture capitalists who lose out if those sites fail: The consumer loses. So I really hope my prediction is right.

Reader Mara writes:

My husband and I are planning on flying to Milan from Houston later this fall using US Airways miles, and I’m wondering what the best option for connections would be. The agent tells me we can connect in Philadelphia, or there are Star Alliance flights we can take with Lufthansa, United, or Austrian. We know from reading your site that London Heathrow is bad for connections, and we would love some advice on where to change planes most conveniently. What should we avoid? Unfortunately there’s no Houston to Milan flight we can take! Thanks!

I applaud your strategizing, Mara, and I think you’re well on your way, simply knowing that Heathrow is a place to avoid. (Don’t believe me? Watch the video.)

There’s no nonstop Houston to Milan, so you’re going to be changing planes for this itinerary. So the question is, as you suggest, where to do it.

My general advice for travel to/from the United States: Try to avoid changing planes upon arriving in the US from overseas. You go through passport control and customs at your port of entry, not your final destination, so you have to claim your bags, possibly submit them to search, re-check those bags for your connection, probably change terminals, and hope you’ve left enough time to make the next flight. Not so in most of Europe: Connections are much, much easier in Europe, with customs inspections at your final destination rather than your entry point.

At the same time, the last thing I want to do after an overnight flight is to get onto another plane. Sure, I’ve done it, and sometimes it’s unavoidable, but my preference is always to have the overnight long-haul end at my destination. On overnight flights, try to arrive at your final destination, instead of at a hub requiring a connection.

So, practically, what does this mean for you? On your flight TO Italy, I would make connections in the U.S. and fly over the Atlantic direct to Milan. On the return, I’d make my connection somewhere in Europe and fly the long haul straight to Houston.

A caveat: These itineraries will usually involve different airlines on either end. That could get pricey for cash-money fares, even with codesharing. Try ITA’s search tool to find the best connections, and to get a sense of prices. Kayak.com may be of help, too, for mixed-airline itineraries.

But you said you’re using frequent flyer miles. Good! This is one of the less-celebrated benefits of the “free” ticket: You can mix your itinerary, with one airline going over and a different alliance member coming back. Use that flexibility to your advantage. And note: You won’t be able to view all the options online. You have to call the airline that you have the miles with — in your case, US Airways.

A quick search on arbitrary dates yields a flight from Houston to Philadelphia, and Philadelphia to Milan (all on US Airways). Coming back, consider Lufthansa from Milan to Frankfurt, and continuing from Frankfurt to Houston. Those flights follow the rules I set out, letting you avoid connections in Europe in the morning after your arrival, and skipping the tense fear that you might not make your connecting flight in the US, once you’ve dealt with Homeland Security’s passport control and customs inspections.

Either way you go, good luck, safe travels, and enjoy Milan!

(image)

Upgraded: Kayak.com introduces alliance-based search
Aggregator Kayak.com tweaked its search tools ever so slightly, allowing you to sort by alliance (Star, oneworld, Skyteam) and not just by airline. But you can only sort it that way AFTER you’ve the basic search. (You can search preferred airlines up front, so why not alliances? Meh.) Orbitz has allowed alliance search for some time, but this is the first aggregator that I’m aware of that’s doing this.

Upgraded: Hertz’s environmentalist credibility
Last September, Hertz rolled out its “Green Collection” of rental cars and I was thoroughly unimpressed. Buick LaCrosse? Come on. Where were the hybrids? Well, it took nine months, but Hertz finally got around to buying more genuinely eco-friendly vehicles, with a purchase of 3,400 Toyota Priuses (or is that Prii?). That’s more like it.

Upgraded: Wine in coach. Viva jetBlue!
JetBlue is serving up some slightly more interesting wines than usual the usual coach fare. Thanks to a partnership with Best Cellars, the airline is giving their all-economy class passengers a slightly better guzzle. Choosing wine for coach can be challenging, since it has to be a) cheap, b) in tiny ready-for-sale bottles, unlike in premium cabins, and c) pair-able with a wider range of foods. I hadn’t thought about that last one before: After all, the wine in business and first can presumably be paired with the menu (though that’s not always obvious). But in coach, a wine demands “versatility in pairing with a wide assortment of airport meals people bring on planes, including pan pizzas from Pizza Hut and Taco Bell burritos with chicken and mole sauce.” (Taco Bell has a mole sauce? Really?) Either way, good for jetBlue, and good for their wine-imbibing passengers. (Thanks Tyler!)

Downgraded: US Airways right to serve any wine
Unlike jetBlue… US Airways, which got into trouble for selling booze without a license in New Mexico a few months ago, and which has been serving the sauce with a temporary scrip since then, was denied an extension of its license this past week. Tough break. BYOB, anyone?

Upgraded: Marriott; Downgraded: Ian Schrager (or is it the other way around?)
Look, I happen to like Marriott hotels for what they are: Consistent, clean, competent, and overall comfortable spaces to spend the night. (4 C’s!) They usually don’t have too much bling or pizazz, though some of their big-city properties have that 1980s glitz that has an odd appeal to my mid-to-late-30s, graying-gracefully, receding-hairline self. So when I hear that they’re teaming up with Ian Schrager, king of the boutique hotel, to create a new boutique-y brand, I’m skeptical. It seems like a late-to-the-game attempt to create a “W” chain within a chain. If it adds a little funk to the Marriott decor, great. (Bye bye brass fixtures, please!) But it also smacks of desperation. And isn’t Ian Schrager past this? Seems like he’s here to cash in while the cashin’ in is good.

Upgraded: WestJet’s honesty; Downgraded: Little old ladies’ pensions
Canada’s WestJet (hearts) little old ladies. Not because they’re nice grandmas, but because they’re walking piggy banks, and the airline’s got a hammer. Consider this nugget from the airline’s president:

“There would be a little old lady coming up and she’d have a table and she’d have a chair and she’d have six or seven bags and we’d say ‘Yeah, take it on the plane. No problem.’ Now we’re actually going to charge a little bit of money for taking that table and chair and those extra bags on board. And that incremental revenue that we extract from that little old lady is very, very profitable to us. Some 85% goes to the bottom line.”

Good for him, for saying publicly what other airline executives discuss privately. So I guess the business traveler isn’t the company profit center; the rarely-traveled senior citizen is. Bank it.

Upgraded: Amputees and their TSA experience
Got a prosthetic? The TSA wants to make your security checkpoint experience kinder and gentler. Good! On the other hand…

Downgraded: Sippy cups, and TSA cinema verité
A former Secret Service agent reports that she was harassed when she accidentally carried her child’s sippy cup of water through security. Stupid enough, but it gets more absurd: The TSA actually released a silent security tape of the incident, labeled “Mythbusters,” in their own defense. Feel free to view the videos, read the incident report, review the embarrassed mother’s story, and decide for yourself.

Upgraded: Demolition
Let me make myself perfectly clear: I want to help destroy this hotel. I’ve never been to it, but I want to help Spanish hotel chain NH Hoteles wreck the Alcala Hotel in Madrid. The company is holding a contest to see who can take a sledgehammer to the joint. Only 30 lucky few will get to play rockstar-cum-wrecking ball. Let the spirit of Keith Moon guide you.

Indeed, this was my own pet peeve with Travelocity’s flexible search. You start with a great fare to Paris and when you finish clicking, your fare went up $300 — $100 in taxes (expected) and $200 in fuel surcharges (suprise!). Often, Travelocity would come back with a message like “We found a lower fare for you than the one you selected.”

(The change also affects the international component of Travelocity’s Dream Maps. Interestingly, you can still see fares to international locations posted on the maps, but you can’t go the next step to find airlines or book them.)

I part company with SmarterTravel’s blame game: I actually think the DOT was right in pressuring Travelocity to offer a more transparent fare search. The existing product was misleading. It’s Travelocity’s fault for not configuring their fare search product in a way that includes surcharges. Fuel charges are a specific, identifiable line item in building a fare. Why can’t it be included in a search?

But for those who loved that flexible international search, now gone, what are the alternatives? Here are my picks, ranked in terms of similarity to Travelocity’s defunct search.

1) Zuji
(Update: Zuji has killed the old flexible search-by-fare feature. The original post remains below for the sake of posterity, but this feature has been disabled. It is replaced by a +/- 3 day flexible search, which is not nearly as powerful. Skip it.)
Outsource! Zuji is Travelocity’s Singapore-based subsidiary, and it looks and feels much like the American site. And guess what: the international flexible date search is still there. The site is in English, and results are in US dollars. (If you’re based in the US, choose “other” for a country on the first page.) Some airlines are missing (but they were missing from the flex search on the US site in the last few months, too). Suggestion: Run your search on Zuji, then actually book the specific flights you find on Travelocity or elsewhere. Booking on Zuji may work, but you’ll incur higher booking fees plus extra charges for using a credit card overseas.

(Update July 29: A reader e-mail asks about Zuji and Dream Maps (referenced above). I can’t find a Dream Maps equivalent on Zuji. However, since Dream Maps will still show base fares (for now), but won’t let you click through to see airlines or schedules, here’s my advice: Use Dream Maps to find a good base fare in your desired region. If you see one, do a flexible date search on Zuji for that particular destination.)

2) FareCompare
On the plus side, FareCompare’s search acts much like Travelocity, except it’s organized by fare, not by airline. The downsides: It doesn’t show total prices (will it be targeted by the DOT next?). It also doesn’t let you book directly, but refers you to the big online agencies, where the price is often very different from what FareCompare quoted. Finally, it’s missing a number of smaller (but still mainline) international destinations.

3) ITA
The engine behind Orbitz, Continental, and others, allows you to search for fares to just about anywhere in the world, and it shows final prices including all taxes. It also finds codeshares and mixed-airline itineraries that are often good values. Its “month-long search” isn’t as broad a search as Travelocity’s, especially because you need to specify the length of your stay within narrow ranges, but it’s worth checking. But … it won’t let you book anything. You’ll need to go to an airline website, online agency, or traditional travel agent to buy the ticket.

4) Kayak
Kayak allows flexible search to international destinations, but only within 3 days of your specific dates. Some reliability problems here, too, for international fares that are quoted well below what the target sites actually charge. It’s not the free-for-all price-first dates-later approach of Travelocity (or Zuji) but it’s an option to consider.

Two incremental improvements to the world of travel searches. Two of my favorite sites have added features:

FareCompare.com has gone live with their historical price data on fares between cities. Want to see how current fares stack up? Do a search for city pairs, and you’ll see the price trends for the last 12 months. If the slope is heading up, don’t be surprised, given the price of oil. But if a current fare deviates below the average (black) line, it’s probably a good fare, and you may want to buy. See here for a tutorial.

Fare metasearch/aggregator Kayak.com added flexible date searching to their arsenal of tools. Not a shocker for users of Travelocity, Orbitz, etc., but this is the first use of flexible searching on a site that searches multiple travel sellers’ inventories. Another reason Kayak is my favorite among the aggregators, previously reviewed here. Minor nuisance: registration is required in order to use the flexible-date search feature. (WHY???)

Note that I went the next step and also reviewed aggregator hotel searches… Let’s see if they follow suit and do the same!

(snideness: off)

AP’s Jesdanun agrees with my assessment of Kayak as the superior airfare search, but BusinessWeek’s Lacy downplays Kayak and instead favors SideStep for its downloadable toolbar “big brother” feature. This is a reason NOT to like SideStep if you ask me. I just don’t trust these browse-along features to protect my privacy. Call me paranoid.

In aggregator news, Mobissimo has in recent weeks made some improvements, broadening the number of sites they search (and pitching the means by which they conduct their searches.) Their recently launched India-based site is a big move. But I still just don’t like their user interface, their comparative lack of information, or their lack of controls. It’s getting better, but it’s not there yet.