The 8800M would cause the thickness of the MBP to increase. That would be a bad move for Apple, so it's unlikely we'll see the 8800M.
STILL, I would like something faster than the crappy 8600M.
not if they slim the 8800M down, but I don't think that's possible. If Apple truly wanted to move to a more powerful graphics card, they would find an alternative to it.
How likely is it that NVidia slims down the size and heat of their graphics cards as time goes on?