Xbox One being able to play Xbox 360 games is something a lot of folks want to see, and Microsoft is definitely looking into it. With Build having just taken place in California you can bet that the question came up in one of the sessions. It was put to Partner Development lead, Frank Savage, by a member of the audience, and garnered this response:
"There are, but we?re not done thinking them through yet, unfortunately. It turns out to be hard to emulate the PowerPC stuff on the X86 stuff. So there?s nothing to announce, but I would love to see it myself."
Full story from the WPCentral blog...