The Case-Shiller Home Price Index came out today, and it showed that home prices fell 15.4% in the second quarter nationwide, and this just puts more pressure on anyone falling behind in mortgage payments. A homeowner that has a loan worth more than their mortgage often finds it easier to just walk away from a home rather than sell it, so until we can see some price stabilization, the glut of homes on the market is likely to grow. Keep in mind that a lot of the adjustable loans are still set to adjust, so again, the pressure on prices will likely continue.
Note: Commercial Building prices seem much steadier. The problem I observe is not the Sales price being too low, but the Listing price of many properties being above market value.