This has been discussed in previous posts. As we have seen previous real estate cycles tend to take approximately 6 years. There already have been certain housing types in various regions that have had major price depreciation already, like in the 20% range. (See UTC condos)
Again, what we have not seen are drastic price reductions by sellers, as well as lenders who have foreclosed and are offering the property for sale. They just are not pricing aggressively yet. Similarly inventory has dropped off by close to 30% from the summer highs. This has been due to sellers giving up, and seasonal adjustments typical for this time of the year.
Finally I think most people who have posted here only forecast single digit drops for the next year as well. We really need a major catalyst to get the bump down you are hoping for. With the 10 year treasury being so low, our or my biggest fear is that distressed homeowners will simply refinance out of whatever mess they are in.
As I am a future buyer, this is not what I want to happen but it is what I think will happen. We just have to be patient. This spring will be a very interesting time. Cross your fingers for high inventory and slow sales.