The research firm found that Kayak visits were up more than 6,000 percent from October through April, while Farechase showed a 659 percent increase, Mobissimo also had a 350 percent gain, and Cheapflights was up 56 percent. Overall, the travel market share of visits to those four meta search engines picked up 304 percent in the last six months, while that of the top five online travel agencies--Expedia, Travelocity, Orbitz, Yahoo! Travel, and CheapTickets--increased by just 11 percent.

Still, the online travel agencies see far greater overall traffic than the meta engines. For the week ending May 7, the top five travel search engines accounted for just 3.14 percent of all visits to the Hitwise travel agencies category, compared to the top five travel agencies sites, which accounted for 60.44 percent of all visits.

Bill Tancer, vice president of research at Hitwise, indicated that search engines stand a chance of continued growth if they can add the value they're promising. "If travel-meta search engines deliver on their promise to efficiently find the lowest prices, then it is possible they will quickly and successfully insert themselves into the travel-shopping value chain," Tancer said in a statement.

But some analysts and industry representatives questioned any conclusions one might draw from the study's findings as well as its methodology. Diane Clarkson, Jupiter Research analyst, noted the problem with comparing the market share growth of a maturing market to an established one. "To be celebrating a significant share increase over the last six months by the search engines, many of which didn't even exist six months ago, might be a little misleading," said Clarkson. One analyst who asked not to be named commented that while the Hitwise study is based on click-throughs, a far more accurate measure of success would be bookings, or conversion rates.

The study also found that the major search engines like Google and Yahoo! play an important role in driving traffic to meta-search sites. Yahoo!'s Farechase received 39.3 percent of its visits from standard search engines for the week ending April 30, 2005; Cheapflights received 24.3 percent from search; and Kayak 16.6 percent, according to Hitwise.

"What some of the new travel meta-search engines lack in brand equity and reach, they make up for in search marketing and optimization within the landscape of the traditional search engines like Google," Tancer said in a statement. "Their product is essentially robust and sought-after content, and that is the lifeblood of search engine functionality."

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