For the first time in recent years, the price at the gas pump - and the specter of higher prices to come - has spurred a significant online shift in car buyer preferences, away from larger vehicles and toward smaller, more fuel-efficient cars. Vehicles such as the Ford F-150, the Chevrolet Tahoe, and other large SUVs such as the Nissan Armada and Toyota Sequoia - perennial favorites among online shoppers -- have suffered double-digit declines while at the same time, smaller more fuel-efficient cars such as the Honda Civic, Mazda3 and Toyota Prius have enjoyed robust growth. The shift is also apparent in the types of SUVs people are requesting - smaller SUVs have remained relatively stable, while large SUVs have declined sharply.

It doesn't mean that Suburbans are going the way of the dinosaur - at least not yet, and probably not ever. Most automakers are reporting robust sales for large vehicles, the result of an improving economy and continuing incentives. But in the face of increasing sales numbers, the online shift indicates that shoppers are placing a higher emphasis on fuel economy during their buying decision, that there has been widespread adoption of hybrid vehicles, and that fuel economy is no longer solely a "pocketbook" issue, as people are recognizing the value of using fuel wisely.