I actually think this could work out fairly well for Obama.
The polls have shifted due to the convention and VP bounces for McCain. Now, the longer the media is focused on he and Palin, the longer the bounce lasts, and the longer the bounce lasts, the less of it Obama is likely to recover before the debates. With this being the new focus of the media, a lot of the attention that Obama has lost has shifted back.
Now here is where is gets tricky for him. He has to convince the voters that the Republicans are attempting to distract them. He had stated before that the Republicans would attempt to distract the voters from issues at hand. He HAS TO use this opportunity to hammer them. What he said today was a decent start, now tomorrow and Friday he needs to blast them. Saturday and Sunday he should more or less lay low since those are slow days as it pertains to the media anyways. Then Monday come out and really start pressing on the economy and other issues and completely stop the "lipstick" talk.
This does two things, keeps the media attention on him for four days, and allows him to at least appear to take the high ground. If he is able to regain the lead, he can coast into the first debate where if he has a good showing he can once again be in the driver's seat.
That's a basic summary of what I think would be the best course of action over the next week.
It also wouldn't hurt for him to really start throwing some serious cash into Florida in the very near future. Maybe stop spending anything in North Carolina.