im not hung up on specs.... even IF it is scaled back to 720 on the xb1(not saying it is) we know the xb1 has a ton of computing power leftover... like we ar still running a modified 360 at this point(imo)
i think ive touched on this subject before as well. but ill put a small idea out to think about. if the bandwith/internet is not streaming fast enough what would it matter if its 60fps at 720 or 1080??? only thing its going to do is make the game feel glitch or laggy.
if the ui itself is in 720 at 60fps so it can cope with the transition from tv,gaming,netflix,apps ect ect,skype, whatever you have running than we are talking about non moving images that have a ton of clarity and are unnoticable.. i run a 4k tv and i honestly cant tell the difference in 1080 or 720... forza5 is clear and crisp ac4 black flag runs great at the images/world look sweet.. bf4 looks good but when allot is going on you can get frame rate drop.. which i have... but still for the most part in normal gaming it is fluid..
the ui has room to grow on both ends... ps4/xb1 developers are just getting the systems running and figuring out how the masses are useing it and getting data daily with issues/glitches and raw data.. we still have yet to see major next gen stuff which is fine.. early adopter syndrome... but i am happy that xb1 is working as well at it has for me.
microsoft had issues with the tile program/ui on windows/laptops.. and that was a major worry a broken ui... heck most everything on microsofts end has gone near flawless.. ui,gaming,apps,tv... im happy happy happy....