Everyone I personally game with is excited about, and switching to, 4th edition. So no problems there. I will probably have an issue around September, when we start organizing our university's gaming convention. D&D is traditionally our biggest draw, and I'm worried that the game masters who sign up to run D&D events won't choose their system in the same proportion that our players would like. I really have no idea what those percentages will look like, but it could be a concern.
btw, the convention is OwlCon, held in Houston at the campus of Rice University in early February, if you're into that kind of thing.