"3G is the next generation of our wireless network, following our current GSM network. In this early phase of our network evolution, 3G is a new technology for carrying wireless voice calls and supporting existing data capabilities on our network. In future phases, this next generation network will power 'high-speed' (3G) products and services that connect customers in new and exciting ways. ... Inform customers who are interested in high-speed data that the first phase of our 3G roll out supports voice only." [Emphasis ours]
No word on when T-Mobile actually plans to turn on the faster data, but for everyone who hasn't already jumped ship -- hoping against hope -- the wait continues.
P.S. -Don't believe everything you hear about this kind of thing being status quo. Every single major US 3G network -- including Cingular, Verizon, and Sprint -- went live as either data card-only (with phones added later), or data and voice together.