T-Mobile US announced that it will officially offer the Sony Xperia Z (http://www.gsmarena.com/sony_xperia_z-5204.php) in the "coming weeks." The Big Magenta will be the only carrier in the United States to offer Sony's water-resistant Android flagship.
(http://cdn.gsmarena.com/vv/newsimg/13/06/xperia-z-tmo/gsmarena_001.jpg)
As far as specs go, the T-Mobile exclusive Sony Xperia Z will be no different than the international version which we extensively reviewed (http://www.gsmarena.com/sony_xperia_z-review-887.php), save for support for the carrier's brand new LTE network. The highlights include a Qualcomm Snapdragon SoC with 1.5GHz quad-core CPU, 5" 1080p display, 13MP Exmor RS camera, and Android Jelly Bean.
The Sony Xperia Z for T-Mobile will be available with the carrier's Simple Choice plans. Exact pricing and availability are yet to be confirmed.
Source (http://newsroom.t-mobile.com/phoenix.zhtml?c=251624&p=irol-newsArticle&ID=1830747&highlight=)
GSMArena.com