The new announcement from NASA makes life on Mars a much more realistic potential. With not just geologic evidence that water once existed, but the possibility that it still may be there (as a semi-frozen slurry embedded under the soil), we even have a chance at current life! After all, we have remnants of previously extant forms living in deep-sea volcanic vents here on earth, which could never survive conditions on the surface. Once life gets a foothold, it doesn’t let go without a serious fight, no matter what conditions it has to evolve to meet.
Here are a few links to bring you up to speed on the latest developments…
http://www.jpl.nasa.gov/index.html
http://www.space.com/marsrover/
Of course, if there IS life on mars today, don’t expect to talk to it anytime soon. Best bet is it would be in the viral or bacterial form. And while both of those formats have the theoretical potential for intelligence (see the writings of W.Gibson, N.Stephenson, and C.Willis for a few beginning examples), we can’t communicate with the ones in our own biosphere yet. How much more difficult would it be to communicate with those from a totally different evolution?