T-Mobile is rolling out its 3G UMTS/HSDPA network today here in New York City, with plans to announce it in other markets across the country in other large cities throughout the next couple of months. The launch supports both voice and data services, and four phones already support the UMTS network in T-Mobile’s store, although none are new. While we were looking forward to some sort of over-the-air-music or -video announcement as well, T-Mobile says that customers will see increased call performance, but data speeds will be limited to T-Zones and Web-browsing content at this time. The first high-speed downlink packet access device (HSDPA) will be available in “the coming months,” so for now, users with the following UMTS devices will reap the most benefit from the new launch: the Nokia 3555 (free), Nokia 6263 (free), Samsung t819 ($79.99), and the Samsung t639 ($49.99). We have a device on the way, so stay tuned for a hands-on with the carrier’s new 3G network. Congrats, T-Mobile.