You can safely file this under "who knows?" at this point, but it seems that the FCC has just passed a new HTC PG86300, also known as the HTC EVO 3D, complete with a GSM radio and T-Mobile AWS 3G/4G bands (1700/1900). Other than missing CDMA and WiMAX, the phone is identical to the EVO 3D currently being offered by Sprint, including the same 4.3-inch screen, the same dual 5 MP cameras, and the same 1.2 GHz dual-core processor.
This is not beyond the realm of possibility, as HTC has already announced the upcoming release of the EVO 3D overseas, but it is interesting that Sprint would be willing to give up its own exclusivity here in the US. Also interesting is that HTC would, in effect, be competing with itself on T-Mobile – by the time this would be released, there will already be two HTC dual-core superphones on T-Mobile (the Sensation 4G and the recently announced MyTouch 4G slide).
We'll be sure to keep an eye on this story as it develops.[Cell Phone Signal via Android Community]
Update: As pointed out by Android Central, this does not necessarily mean that T-Mobile will pick up the HTC EVO 3D. Other possibilities include Canadian carriers Wind Mobile or Mobilicity, which also use the 1700 MHz band.