"I think we are very near to the end of the housing downturn," (AP News).
The just released New Home Sales Report shows a months supply of 10.9 months (quite high). And new home sales for August 11.5 percent below the revised July rate.
Historically, most housing busts in the United States lasted 3 - 8 years. Since this housing boom was much larger then previous booms, the bust is likely is to last on the longer side. However, some say because of much better access to information (Internet, more statistics etc) the bust is happening faster. Since, late 2005 / early 2006 was the peak, this bust has lasted about 3 years. Likely bottoms, in most bubble markets, should occur between late 2009 to 2012.