Many people don't realize how powerful interest really is.  We figure we buy a home for 200,000 we are paying back 200,000 and a little extra.  Well that little extra is really a lot extra.  While I was doing some reading a few months back I came across this article on www.inman.com.  While most of us expect interest rates to jump up at some point few buyers realize how much that really changes the amount of money they pay back over 30 years.  So if you are reading this and your sitting on the fence, it might be enough to push you over the edge.  Rates are still low, extension of the tax credit is still an unknown at this point, but after reading this, the potential 1% or 2% change in interest rate is more than enough to make up for the 8000.00 dollar tax credit.

"Get buyers off the fence and under contract. Use your marketing materials to let potential clients know that now is the best time ever to buy. Even if prices drop further, show buyers how an increase in interest rates can easily wipe out any savings they would have experienced by waiting.
For example, on a $200,000 loan, an interest-rate increase from 6 percent to 7 percent will result in an additional $47,340 in interest payments over the life of a 30-year loan. This means that a one-point interest-rate increase will cost the buyer an additional 23.7 percent in payments. If interest rates increased from 6 percent to 8 percent on a $200,000 loan, the increase in interest would cost the buyer an additional $96,620 over the life of the loan. In other words, the buyer would pay more than 48.3 percent of the loan amount in additional payments.
While prices may still be falling in some areas, in most places the amount of inventory is starting to shrink. As the inventory declines, prices will stabilize. The probability that prices will decline an additional 23.7 percent to 48.3 percent is highly unlikely. On the other hand, the probability that interest rates will increase appears to be quite high (Bernice Ross, Inman News 6/8/09).

The Complete Article

I'm sure now that you've completed reading what Bernice has calculated that your thoughts on interest have probably changed.  Don't be alarmed if you missed the tax credit, because rates are still competitive.  You still have a chance to score a 5.5% interest rate or better.  It's still the right time to buy, we just don't know if that magical 8000.00 will be available or not...and really lets face the facts they are just giving you 8000.00 of your own money because it will get recouped via taxes at some point.  Consider it more like a cash advance.