Now before you get all in a tizzy about the ramifications of the Magic showing up on the FCC site w/o support for T-Mobile USA, bear in mind that it is dead common for foreign variants of U.S. bound devices to be tested by the FCC even though they won’t ever be sold here.
This doesn’t mean, necessarily, that T-Mobile won’t be getting the Magic (G2), or that AT&T will. Chances are exceedingly high that the FCC will get a second version of the Magic/G2 to test that will include T-Mobile’s AWS 3G support.
It does reinforce the expectation that the device, in one form or another, is headed to American shores, though.
If you are so inclined, you can look through the FCC documents yourself.