Brian Cox on Kepler 22-b: And if we are alone?

In its short tenure in Earth-trailing orbit gazing on the stars in the Cygnus-Lyra region of the Milky Way and looking for the tell tale blink-blink of other worlds momentarily blotting the star light reaching its open aperture, Kepler has dramatically expanded the number of candidate planets known to us. Isn't it amazing that in the short period of time that we've been able to detect these new worlds, information pointing to their existence now routinely pops up in the data?
But even if we find out that Earth-like worlds with watery surfaces are likely to exist, what is the real world, practical application of knowing that another planet like ours orbits in the habitable zone of its parent sun? After all, at tens to hundreds of light years away, no one is ever likely to see them at close range. Still, as Brian Cox explains to the BBC in response to the discovery of Kepler 22-b, it's one of the great questions ever, "are we alone?" And if we can find life elsewhere, particularly microbial life in the irradiated soil of Mars or beneath the ice of Europa or in the methane seas of Titan, to take three examples, ...