Personally yes, think about it if he has any serious aspirations of running in 2008 he cannot allow the Dims to filibuster he must support his own party.
I'm not so sure. I think he will pick the most populist stance and go with that. I hope it is the same as the Republican aims.
Being pro choice though, I believe he does not want to see Alito on the Court. One of my New Year's prediction is that he will not stop a filibuster if the Dem's are dumb enough to do one.
I hope I am wrong.