Even though prices are now rising as fast as in the bubble years, national home prices today are 7% undervalued – compared with 39% overvalued at the height of the bubble in 2006 Q1.

In only 8 of the 100 largest metros are prices overvalued. Orange County, Calif., and Austin, Texas, are the most overvalued, but only by 9% and 7%, respectively.

"To see a bubble, you first need to know what you’re looking for," explains Trulia chief economist Jed Kolko.