In the U.S., the roll-out of the national LTE network is on the agenda. In addition, T-Mobile USA has entered into an agreement with Apple to bring products to market together next year.
The T-Mobile announce is part of a larger press release detailing future upgrades and expansion. It's not simply an announcement about Apple, so presumably that's why it's so vague. It's safe to assume, however, this means the iPhone and likely iPad will be coming to T-Mobile next year.
It will be interesting to see how this rolls out. Part may be dependent on T-Mobile's infrastructure, but also Apple's roadmaps. When Apple expanded to Verizon, it was a mid-year update on the iPhone, but wasn't brought to the iPad until the next update. We'll have to see if Apple/T-Mobile introduce something in the interim or if it will be a part of the next iPhone and iPad.
