People who are not technical, but pay attention will notice the loss of clarity when going from 1080p to 720p, it's like getting prescription glasses if your eye sight is not amazing... however you will never see it as evidently as when games went from VGA (320*200) to SVGA (640*480) that step was HUGE!
What we need to reach before resolution becomes a non issue is the densities we have on phones and tablets now (around 300 PPI for computer screens would be amazing and I guess 150PPI to 200PPI for TVs would settle it) I mean, when we are on 4k it will be like paper, when an image is up-scaled a bit I don't think it will be too smudged...
Now very few people have 4K TVs and neither home console can output their game at this resolution, at least not a demanding game! so the discussion for 4k is pretty moot :-/
I think expecting 1080p in 2014 is just reasonable, as should be close to 60fps (I mean, we have Tomb Raider on the PS4, I would be able to live with games that look only like that but are silky smooth...)
I think spacial resolution is as important as temporal resolution.







