You can count me as one pollster who thinks that an immediate post-health care Obama approval bounce is very unlikely.
On our last national poll 97% of respondents who disapproved of Obama's job performance said they were opposed to his health care plan. Why would its passage with no Republican support cause those people to go back to liking him? If anything it could make them dislike him more.
In the long term if health care is signed into law and looks like a success it could help Obama and Democrats- but whether that visible positive outcome occurs by election day 2010 is doubtful and it's certainly not going to happen in the immediate future.
I think Obama's numbers are going to stay about where they are until people at the household level really start feeling that the economy is better- economists telling them it is will not do the trick.