Some of those reading this may be familiar with planetquest, which is part of an active search by astrobiologists (and yes that is a real scientific field) for earth like planets. It is a very interesting study which in which I plan to be involved. The reason I am mentioning this is because I found a really cool 3-D map of all the stars with planets orbiting them. So far only one planet small enough to be a terrestrial planet has been found so far (most are the size of Jupiter or the gas giants). Of course one of the gas giants in the habitable zone may have a large moon which harbors some form of life.
There are also some planets which have circular orbit which might mean there is a small undetectable earth sized planet orbiting that star. You see, a Jupiter sized planet in a very eccentric (comet-like) orbit would carry off any poor unsuspecting earth like planets into the far reaches of its Solar System making it inhospitable for life. So if there are no Jupiter sized planets in eccentric orbit there might be a planet orbiting the star which is earth like or perhaps a large moon orbiting the Jupiter like planet capable of harboring life.
Many of these worlds could be future homes for our descendants