The move pits PriceGrabber against the likes of Orbitz, Travelocity, and Expedia--as well as large portals like Yahoo! and Google, which are vying for a piece of the online travel market. Research firm eMarketer Thursday released a report estimating that online travel would reach $65.4 billion this year.

Consistent with other vertical search models, after entering city and date information, PriceGrabber Travel displays available fares and rates for thousands of flights and hotels from many different sites. Once the results are displayed, travelers can choose from sorting options such as price, flight times, and hotel name, among others.

Information on areas ranging from hotel amenities to in-flight entertainment options is available either alone or as part of PriceGrabber's side-by-side comparison.

PriceGrabber's travel vertical also offers "FlightStats" ratings, which give a ranking of each flight's performance relative to other flight alternatives. The rating is statistically derived from on-time percentage, average delay, and the number of flights operated in the past 60 days to give an accurate measure of on-time performance for every flight.

At the end of October, Yahoo! launched a set of travel planning tools, which shift Yahoo! Travel's attention from expert reviews to the opinions of users and the Web communities they trust. The service, coined Travel Planner, brings together existing offerings such as maps, bulletin boards, and local listings with Flickr photo-sharing features and user reviews. At the same time, Google debuted a search feature for specific flight inquiries. The feature displays shortcut links between two locations at the top of the search results to travel providers. Once a user enters their preferred travel dates, they can click on a travel site link to generate a specific flight search.

PriceGrabber powers comparison shopping services for MSN Shopping, AskJeeves, About.com, and Comcast, among others.

At the end of last year, About.com began rolling out PriceGrabber's comparative shopping information--citing some 10.5 million products--on many of About.com's 23 content channels, including shopping and style, home and garden, and health and fitness. In June of this year, PriceGrabber formed a strategic partnership with Microsoft's MSN to add the shopping site's listings and review database to MSN's shopping vertical site. The new listings will go into effect before the fourth quarter and are part of MSN's preparations for the end-of-year holiday shopping frenzy, said MSN Shopping Group Programming Manager Chris Jolley. The deal added millions of listings to MSN's shopping categories.

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