Eventually, T-Mobile hopes to have this faster service available in 90% of the top 25 U.S. markets, and offering the faster speeds is something the mobile operator is expecting to do in earnest sometime next year. For now, it will have 10 x 10 service in 40 of the top 50 markets by the end of this year. And while other carriers are also looking to speed up data delivery, Verizon (adding AWS to its LTE spectrum) and Sprint (tri-mode LTE aka Sprint Spark) require the use of updated phones. AT&T's faster LTE service will also require new phones. With T-Mobile's 20 x 20, its current batch of LTE-enabled handsets will work just fine, thank you.