Plenty of Earths await discovery: By Jonathan Amos BBC News science reporter, in Birmingham.

http://news.bbc.co.uk/2/hi/science/nature/4411865.stm

Quote: “British researchers are more confident than ever that there are "Earths" out there waiting to be discovered. The scientists say perhaps a half of all the known planetary systems today could be harbouring habitable worlds. It must be said most of these systems are strange places where supergiant planets orbit close in to their stars. But Barrie Jones and colleagues say their modelling work suggests that even with this oddness, there should be room for small rocky planets.”

The argument seems to be that, even in systems that have massive planets orbiting close to their star, may still have small rocky planets, including wet planets, because at the time the giant planets sweep inwards towards the star the formation of small earth-like rocky planets is incomplete. The formation of earth-like planets goes ahead after the super-giant planets have become established.