According to the National Automobile Dealers Association (NADA), Americans bought 16.5 million light vehicles (passenger autos, SUVs and pickup trucks) in 2006. Unit sales for the year were the eighth strongest ever.
A major reason for the strong sales year was automakers' offering various incentives, including zero-percent financing. Zero-percent financing is essentially an interest-free loan over the entire loan term. During 2006, some makers were offering employee pricing or a choice between zero-percent loans and their historical practice of offering rebates to auto buyers.
You should "run the numbers" to see which is the better deal: low-interest-rate financing (or zero percent, if you can find and qualify for it) or a rebate offer. Both of these types of financing share the same goal of boosting sales for auto dealers and makers.
Zero-percent financing is tantalizing but it may also be limited to only those customers with the best credit histories. In that case, you may wish to ask a dealer or your lender about the availability of a low-interest-rate loan.