The online travel segment grew rapidly over the past three years, and growth is projected to be in the high teens for the next three years. So why are online travel agencies belting up for a bumpy ride?

It is a cliché now, but no less true, in the early days of e-commerce the online travel industry "took off," as millions of consumers booked their own travel reservations. Travelocity, Orbitz, Priceline and Expedia served as models—showing other industries innovative ways to use the Internet to bring better service and pricing options directly to customers.

Even while the US travel industry as a whole staggered following the terrorist attacks of 9/11 — the $206 billion industry is only now recovering, projected to register an annual growth of 5% this year — the online segment recorded huge gains. This year, nearly one-third of US travel will be booked online, with online agencies accounting for nearly half of that total.

Get the full story at eMarketer