Microsoft's marketing lead revealed on Twitter last night that owners of the new Xbox One X will be able to enjoy their Xbox 360 games at a native 4K resolution - 9x the original resolution. On top of that, Original Xbox games will run at 16x their original resolution.
More details are being revealed regarding how we should expect Microsoft's new system to perform. We already know that unlike the PS4 Pro, where games have to be specifically designed to take advantage of the extra horsepower, the Xbox One X will improve games across the board.
The console having a completely different, but significantly more powerful architecture, is starting to show tangible benefits. Digital Foundry have started to compare Xbox One X to PS4 Pro as they get access to third party games supporting the system, but this is the first time we are getting details on how the backward compatible games will run.
I admit I'm pretty excited about playing Star Wars: Knights of the Old Republic and the Dead Space series again in UHD.