That seems unlikely to me. A new XB would be premature I think. Devs are still working on this gen as a baseline target. PS4N is just an optional extra for gamers, but the target is still PS4 and this gen. Would gamers migrate en masse to a new super powered console and require devs to transition to the new target? As I say, it may just be PC-like, running the same games dialled up. What if it wasn't even an XBox, but a Windows Box?!
Could be super powered, super priced, offering a different service and experience, playing XB1 games through emulation and Windows games in full fat, meaning devs just treat it like a high end PC rather than a new console target. Because
I really don't think devs want a new gen to start so soon. Say, on a progressive hardware model, double power every two years with progressive engines rolling up to the next performance target, instead of needing a massive change in creation between last and next gen hardware because the delta is so vast.