It would give no insight into ways of evolution, even if it was a fossilized life form, 1 sample shows nothing about evolution.
Of course it would give us insight into different forms of life, there are still millions of undiscovered life forms on our planet, and each one does that.
It's ignorant to believe life is earth-unique in the first place. You honestly believe with trillions and trillions of other planets in the universe there's no life anywhere else?
See above.
---------- Post added 2012-11-22 at 02:19 PM ----------
Let's hope not. Space exploration is the absolute last thing (the US) anyways needs to be spending one cent on. Unless there's a solution to balancing a budget and fixing the economy up there on mars.