I wrote about the XBox 2 being powered by G5s, then more recently threw out an off-hand remark about Microsoft developing XBox2 on G5s. Except that wasn't apparently confirmed yet. The Inquirer confirms it, with details of the XBox 2 SDK:
The big news to us is that the XBOX 2 SDK has been seeded to developers on dual Apple Power Mac G5 systems running a custom Windows NT Kernel.
My other recent post about the Mac speed advantage, where I talked about Microsoft possibly porting Windows to PPC, now doesn't seem so crazy anymore. The tie-in with Virtual PC and a lot of similar thinking is covered nicely by eclecticism, home of Michael Hanscom, the (former) Microsoft employee that got fired for taking pictures of G5s on the loading dock.
I don't quite know what to say. Microsoft porting to PPC would have seemed inconceivable not that long ago.
Update: the Unofficial Apple Weblog has an IBM memo that seems to be saying that the Apple G5 might have used Intel chips.