Wondering if it's not a rebranding: with Windows 10 running on raspberry pi, what's the catch ? Are they simply abandoning the 9+inch tablet ARM devices?
Microsoft has cut down to basically three versions of Windows that they admit to:
* Windows 10 IoT, which runs x86 and ARM, and is the one that runs on the Raspberry Pi.
* Windows 10 Mobile, which replaces Windows Phone 8, and I believe is also x86 and ARM, for devices under a certain screen size. No desktop, runs the Windows Universal versions of Office.
* Windows 10, which replaces Windows 8 for desktop, and runs only on x86. Has a desktop and runs both versions of Office, desktop and Universal.
RT slotted between Mobile and the full Windows -- it had a desktop, but only for a special ARM version of Office. Now there's a version of Office for Windows Universal, and so you can run Office without the desktop. Thus, the version of Windows with a desktop that can't run any non-Office desktop apps is geting killed. You can either get Windows 10 Mobile without desktop, or full Windows.