I've moved over from D&D 3.5 to Pathfinder and I'm very happy with it. I've tried (bought the books and played) D&D 4th Edition and I'm personally very unhappy with it and the direction it took.
So, I think 5th Edition will have to prove itself before I go anywhere near it. Effectively, WotC have lost me as a customer. They will have to pull something truly impressive out of the bag to get me back.