Ms. Palin's overall favorability ratings have plummeted (not unexpected once people actually got to know who she is and how little she understands).
The Obama/Biden ticket has regained its lead in national polling (a statistically significant lead of 49%-44% in a CBS News/New York Times poll, and a statistically significant lead of 49%-45% in the latest Quinnipiac poll), and the Gallup Daily Tracking poll shows Obama/Biden leading over Palin/McCain today by 5 points, 49% to 44%. The post-GOP convention "bump" for Palin/McCain seems to have been fueled by a renewed excitement among the religious right, and not by any real excitement among Independent or undecided voters.
Meanwhile, on 270towin.com's interactive electoral map, giving John McCain all the current toss-up states, but leaving Pennsylvania out (because at this moment, it is an absolute dead heat), I have Obama/Biden over Palin/McCain 261-256. In this scenario, it all comes down to Ohio (look for GOP dirty tricks there in October or, God forbid, on election day).
But more realistically, Virginia has been trending Democratic in recent years, and trending toward Obama since January, according to Rasmussen, and Obama has a higher favorability rating than McCain in Virginia. Indiana has also been trending toward Obama (although John McCain still holds on to a 2 point lead, down from 4 points in August), and Obama has higher favorability ratings there too.