The problem? Despite already allowing Slingplayers on all other Smartphones on its network, AT&T has forced Apple to ban use of Slingplayer on their 3G network so that the final release app only works on Wifi. Why? AT&T says "the iPhone is not a phone but a computer." The real reason? AT&T is finally coming to grips with the fact they have sold more network bandwidth than they have to offer.
I suspect a class action lawsuit may be on the way, if AT&T does not rectify the situation by late summer. The next iPhone is sure to stress their network even more, and nothing says "push Apple to Verizon" faster than banning apps users desperately want.