I hope for your sake that the bottom is December. I think is will be more like Q1 2009. My reasoning is simple. The next 4 month are huge ARM reset months. The borrower who will default between now and then and who will end up foreclosed up will probably spike in Q3 2008 and begin to fall in Q4 2008. It's going to be another quarter or two after that when supply begins to stabilize with demand and prices get a firm footing and then buyers come out a little more strongly as the bad news subsides.
Cross your fingers for continued low interest rates or the recovery time gets extended. Of course, real estate market conditions are local. In the NW Chicago suburbs the demand is slack, but not terrible. Chicago proper is a lot tougher because condo prices are off the chart and with the demise of the interest only program and neg am programs, who can afford a 300K 1 bedroom or 400K 2 bedroom condo with $300- $500 a month assessments to boot.