Well that sure didn't take too long.  Looks like the T-Mobile HTC HD2 (aka WM6.5's last hurrah) has received a ROM update.

Slight word of caution: we're hearing this isn't 100% officially public yet, but perhaps the final ROM for T-Mo employees/testers, etc. So expect an "official" announcement next week by T-Mobile and HTC on this exact update.

The OS build is bumped to 21892 (a very good build, we might add), updated radio, updated Swype , reportedly more stable and responsive (via XDA forum) and finally, it includes a new app to see your account information. 

If you want to know all of the software changes, here ya go (not for the faint of heart!).

You can grab the download directly from HTC here.

Update: HTC pulled it :-/

Update II: T-Mobile will make the update official on the 18th!

[via TMoNews and PPCGeeks forums]