I think it's going to be jarring to move between classic and Metro modes, but I don't think there's a clear way for Microsoft to alleviate that. I also don't think it's unreasonable to say that there is a tablet paradigm that can live alongside the regular desktop paradigm. I think there are some that expect Microsoft Office and a twitter app to be equally usable via a mouse and a finger and I'm not sure that's entirely reasonable. At the very least, the hacker in me has no problem with needing to break out a mouse and keyboard to really get things done.