Some 150 million consumers visited travel websites in 2005 - 35 percent more than the previous year - and 2005 online travel revenues exceeded $60 billion, 20 percent more than in 2004, with all travel segments posting gains, according to a comScore Networks analysis of the U.S. online travel market. Online agency as well as supplier sites are growing, with agencies posting a 19 percent revenue gain in 2005 and suppliers recording 21 percent growth.

Branded supplier sites captured approximately 57 percent of online travel dollars in 2005, up from 55 percent in 2004. Supplier sites, which accounted for 53 percent of airline ticket sales in 2003, have grown in popularity to capture 58 percent of airline ticket sales in 2005.

Similarly, in the hotel segment, supplier sites have grown from a 52 percent share in 2003 to 59 percent in 2005, with the growth from 2004 to 2005 particularly strong.

On average, travel shoppers visit approximately three sites when planning leisure travel. The dominant reason for doing so is to search for the lowest price. When people begin researching travel services online, the first site that 46 percent visit is Expedia, Travelocity or Orbitz - nearly double the proportion of those (24 percent) who report starting their research at a branded airline, hotel or car rental site.

The top reason stated for beginning at Expedia, Orbitz or Travelocity was efficiency in seeking the lowest price (22 percent), with an additional 17 percent sayin they expect these sites to deliver "the best deal."