In a press conference in Brazil Phil Spencer head guru of Xbox, said

“[Xbox games on Xbox One is] something I want to do, but it is a matter of priority. I would love to have the ability to play Xbox 360 on PC at some point too, so we have different things we have to think about when we plan these things. But it would be great to have support for original Xbox games. So yes, I want it, but we have many other things we want to do as well.”

His words suggest that the ability to play Xbox 360 games not just on the Xbox One but also on the PC. This would seem to be leaning towards the recent Microsoft philosophy of one a unified application structure. There has been plenty of talk recently of playing Xbox One games on Windows 10 PCs and of a Unified architecture but this is the first time we have heard anything of the often neglected Xbox 360 getting this type cross platform play.