BSQUARE just announced that it's going to port a version of Adobe Flash to Android for a "global Tier 1 carrier." This most likely means T-Mobile, if our guess is right.
We've no idea from the press release whether or not Flash will be usable on the G1 that's already available, but it seems like the next phone (the G2?) should almost certainly, definitely, probably, most likely have it. Maybe. [Bsquare via Engadget]