Is the U.S. housing market in a free fall? Values in 20 major cities slid 20 percent in the 12 months ending in January, a record slide capped off with a record drop of 2.8 percent in the first month of this year. Home prices, off 29 percent from the peak in 2006, are now at 2003 levels. And we haven't hit bottom, according to analysts. "Looking ahead, depressed demand, tight credit, rising default rates and excess inventories will continue to lead prices lower," Merrill Lynch economists explained. "We estimate that an additional 10%-15% in downside is still in store."