Microsoft's (MSFT) Bing has recently added a new feature called Price Predictors to its travel searches, which automatically suggest flights based on the best air fares -- and even recommends if you should buy now or hold off for a better price based on how fares are trending. For flexible travelers, suggestions are offered as one types in the search bar. We believe this will have an impact on companies like Expedia (EXPE), the largest U.S. online travel agency by booking volumes, and challenge Google's (GOOG) move into the travel search.

I don't share my colleague Eric Buscemi's enthusiasm for Expedia Inc. (NASDAQ: EXPE). The second IPO in four years for Orbitz Worldwide Inc. doesn't thrill me either.

Online travel is a commodity business where people's sole loyalty comes from whoever gives them the lowest price. While in theory that's great for consumers, that's lousy for investors. The travel sites are big advertisers because they need to convince people that they are different from one another and that they can offer better bargains then each other and the service providers.

The public is bombarded with a confusing array of advertising about where they can get the best travel deals on the Web. Both Orbitz and Expedia offer $50 travel coupons to people who find better prices online within 24 hours of booking a trip on their sites. Airlines make the same promise as do hotels and car rental companies.

If all of these claims are accurate, why should anyone even bother using Expedia or Orbitz?

I realize travel providers need Expedia and Orbtiz because they can't sell all of their excess inventory themselves.

But is that a good enough reason to invest in either company?

I don't think so.