But it still has CDMA :). I have no doubt that such phones will start appearing shortly.
Sprint has a problem with SIMs. There are too many different types because they don't have a sophisticated back end so they put a lot of info on the cards that should be part of the back end business logic. They have neglected that part of the infrastructure so T-Mobile will try to move Sprint accounts over to the T-Mobile system as soon as they possibly can. They can let the two subscriber groups roam on each other's networks for a little while but moving Sprint subscribers over quickly is critical.