It depends. I've stopped to help pigeons in a certain parking lot where people fly through and hit them frequently, and I've stopped for some larger animals, but the odds of such a little creature surviving are so low that I think I would leave it.

Just as a side note, I HATE HATE HATE it when people think they're doing a baby bird a favor by picking it up off of the ground and sentencing it to death...er...trying to raise it. Odds are it was trying to fledge, so just LEAVE IT THERE! *EXPLODES*