Since the very first day it was announced for Europe and Asia, we have known that the HTC HD2 would make its way to the US by the first quarter of 2010. A specific carrier was not named, although the rumor mill was quick to point to T-Mobile, something which was shortly thereafter given credence after the leaking of an alleged internal slide which featured the device. Today a new video featuring a leaked copy of ROM 2.01 proves once and for all that the device is undergoing testing by T-Mobile USA as the boot screen clearly shows the logo of T-Mobile’s “Stick Together” slogan. As for what’s new in 2.01, Windows Mobile junkies will likely love the live preview of files in the Documents tab as well as some much needed spit polish to the music library. Hit the jump for a quick video rundown.