Yep, McCain is bleeding profusely. I think the reason is twofold: (1) The obvious economic meltdown and the public's clear preference of Obama to address it, and (2) The realization by independents that Sarah Palin is an empty (pant)suit. The very few interviews they've allowed her to do have been disastrous.
The electoral vote map is looking very favorable for Obama. Obviously he has to do well in the debates to continue this trend in his direction. I suspect McCain will look old and confused. With the debate flip-flop he has already seriously wounded himself. Is it fatal? A little early to say definitively.