NASA Detects Potential 'Habitable Zone' Planets
In its search for planets outside our solar system, the Kepler space telescope has identified more than 1,200 possible planets. Dozens of those are in the "habitable zone" around their stars where life might exist.
Source: http://www.npr.org/2011/02/02/133443189/An-Update-On-The-Hunt-For-Earth-Like-Planets?ft=1&f=1007