Update: The Tweet you see above has been deleted. Validation!?!?! (Good eye, Mxx!)
We're really not fans of seeing "official" sources break news on Twitter, but so be it. Here you see a translation of a Tweet from @HTC_Ru, HTC's Russian Twitter account. And it clearly says that of the Windows phones currently available, only the HD2 is slated to get an upgrade to Windows Mobile 7. That's something we've been quietly expecting for a while now, especially given the supposed WM7 chassis specs. The HD2 has the 1GHz Snapdragon processor. It's got a capacitive screen. And it's hulking size means I wouldn't want to tell it it'd be stuck with Windows Mobile 6.5 forever.
As for other devices getting an upgrade to Windows Mobile 7? We'll go ahead and say that the bunch we saw recently in that HTC leak are a pretty good bet, assuming they're not actually launched with Windows Mobile 7.