Hmmm . . . the impact, not sure. Probably not much in the polls so fast, but the MSM will shift their focus off of trying to portay Sarah Palin as too green and too stupid. The left has the attention span of a gnat, though, so they might switch back to that mantra in a couple of weeks.
I don't really believe Barack Hussein Obama is more than a few points at the most ahead of McCain right now, but I'd guess this debate will freeze the numbers for a day or so - I think by mid-month McCain will have a lead that will grow and grow and grow - BHO has peaked, probably for the last time. This debate performance just made that happen a little faster, but the voting fraud a la ACORN should be checked.