Ignore 4k. That's a long ways off.
EVERY game on the ps4/xbone should have been REQUIRED to be 1080p/60fps.
If you can't achieve that, your game doesn't pass QC. If you can't achieve that, then you turn down some details.
Due to THAT I don't consider either a "nextgen" (eg 'current-gen') console.
For the same price I bought a PC (in Australia where we pay more for everything!) that can play titanfall at 1080p at 60fps with everything reasonable turned on. As well as every other game. No I don't run 16xFSAA, but I run 2-4x FXAA, 1080p/60 (without drops), 16xAF, and "most" settings turned on (games with silly options like "reflect your face in drops of dew on blades of grass" I turn off). All for $600 (same price as the xbone in AUS). I bought a few logitech wireless controllers and run steam in bigpicture mode on windows 8.1 And I also run xbmc for the full media thing.
I've owned every sony, nintendo, and MS (not that hard) console until "this" generation. My first console (bought with my own money) was an NES. My last consoles were the ps3/360/wii. I'm a HUGE console guy.
But for the next 2-4 years I think I'm "out". Maybe I'll return to the mother ship again