Brad Molen, writing for Engadget:
T-Mobile and Apple have entered an agreement and will be launching products beginning next year. The announcement was posted (nearly as an afterthought, oddly enough) as part of a press release in which Deutsche Telekom spelled out its financial plans through 2015, while COO Rene Obermann also made the announcement in an investors conference. While the two companies have not explicitly given specifics on which Apple devices we can expect to see in a retail store near you, we wouldn’t be surprised to see new products from Cupertino hitting the shelves around the same time as the fourth-largest US carrier’s LTE launch in 2013.
Now the iPhone (and presumably LTE-equipped iPads) will be on all four major US carriers.
Update: Kevin Fitchard writes for GigaOm that T-Mobile is planning to do something ballsy: get rid of phone subsidies. Interesting, but as the article mentions, it'll be a tough sell convincing customers to pay $650 (or more) for their iPhone 5S.