What Microsoft has been saying about Xbox lately strongly implies that this is a Windows handheld designed to solve software and user experience problems with using current Windows handhelds. And signs are pointing toward the next Xbox console coming sooner than the next PlayStation and essentially being a PC running a console version of Windows. Some speculation on my part, but I’m not the only one coming to those conclusions.
It technically does, but you won’t be able to run the Windows Phone 8 app on modern Windows ARM.