In the ever expanding race to discover planets outside of our own solar system, two new planets were recently discovered that are more like Neptune than Jupiter (as most planets discovered thus far have been gas giants like Jupiter and Saturn).  Scientists are becoming increasingly certain that, as our technological ability to locate extra-solar planets becomes more finely tuned, we bring ourselves closer to discovering Earth-like planets — that is, planets of the appropriate size and density to support life and orbiting their sun at a distance which would make the planet habitable.

Since the number of extra-solar planets discovered is rapidly approaching 200, the most recent of which have been smaller than the gas giants we've discovered to date, I believe it's only a matter of time before we begin to locate planets like Earth orbiting distant stars.  In addition, as we continue to realize our galaxy is full of planets of varying kinds, the idea that we are the only life in such a vast conglomeration of stars becomes inarguably more remote.