Michelle's job at the convention was to rebuild her negative image so that she could become an asset rather than a liability for Obama. I think she probably at least partially did that at least by not saying anything to increase her negatives.
I am cynical enough to believe that Hillary's intent with her speech was not party unification at all, but to underscore how much better a choice she would have been. I think she succeeded quite well with her own base in doing that. I am also cynical enough to believe that Bill and Hillary will not be doing ANYTHING to seriously improve Barack Obama's chances in November. I believe they have calculated on how to keep the focus on themselves to this point, and since a great deal of current coverage focuses on them or at least includes them, they have been successful in that too.
If Bill sticks even mostly to his assigned script tonight, the Obama camp will be deeply relieved. And I think they also have their fingers crossed re Biden's speech too as he is also capable of pulling some pretty good gaffes:
No indication that the football arena is off the schedule though, and Fox News this morning said a crowd of 77,000 is anticipated. This will do nothing to dispel Barack Obama's rock star image and won't provide the feeling of closeness, intimacy, and togetherness that is normally there during the acceptance speech surrounded by delegates and supporters, but Obama is capable of giving a really great speech. He can hope that it will wrest the limelight away from the others.