Oh I guess I got that wrong. It seems it's only Photoshop, and then only PS x64 (and maybe After Effects) and XP 64 that's not officially supported.
It's possible though that they've changed that since I last read about it, because XP support by Microsoft had also been extended.

And in software manufacturer terms "runs okay on" and "supported OS" are very different things.
Googling it seems to turn up a certain amount of confusion regarding the whole thing.