Yes, when XBox started out they very intentionally decoupled it from the rest of corporate culture. I'm out of touch with the more recent reorganizations so not sure about where Bing and WP7 are these days, but agree that they're showing positive signs as well.
Bing is run the same way, is it not?
It seems that Microsoft might finally be learning that if it acts as a loosely coupled set of components rather than a monolith with everyone getting veto on everyone else, things work a lot better (and presumably cheaper too). They have all the talent, they just kill it with middle-management (see: Kin).