lets step back into the land of reality. You have ATRAC, FairPlay (har har), Real, WMA, and a host of other DRM infections, and none can play any of the others. If you have a player that can do one, chances are that it can't do any of the others...

...It hurts the users, and hurts the companies making it, but they have their eyes on the big prize. DRM infections are the only way to keep their rivals at bay, lobbing a few bullets at the users is a low price to pay for that.