It is predicted that housing prices will drop a startling 30% by 2014. When the appraised values are so much lower than the market rates, it lowers the housing prices, and it will continue to lower prices. If you are in an area where there are a lot of short sales and foreclosures, it is likely that your property has lost value, and will continue to lose value in the coming years.
Before you sell, go to the county property appraisals office and make sure you know what your property is really worth, and make sure you know the prices your area. You may be able to forecast where your market is heading.