No. The only point reason to go below 720p would be to get 60fps on a very demanding game. But I think developers are more likely to sacrifice fps to stay in the HD range.

I do not expect any games to fall below 720p on the X1 or PS4, as most likely things will be easier as developers get use to the systems.  These systems are a huge boost compared to those PS3 and Xbox 360 dinosaurs! 

Back then everyone was happy with their new HD-ready TV!

Nobody wanted to complain about resolution cause everything was VERY much detailed.

i hope we do

I doubt it. The loss in clarity below 720 would be too great against any additional effects a dev could put in.

Agree with this.   Sub 720p would be a pr issue and more likely to get away with the occasional sub 30fps.

yeah.
Watch dogs on X1 is already 792p at 30fps (and its uncertain if it really is 30fps or if its doing a ryse)
In 6 years time, I can see a game like GTA 7 being below that. Or maybe it will retain 720 vertical pixels but sacrifice horizontal pixels.

I'm sure we'll see some of them. Quick ports, shovelware, some indies, and probably some massive online multiplayer. But if correctly upscaled to 1080p and with anti-aliasing level high enough, they'll look quite smooth, not detailed as higher native res, but at least smooth. No need to panic.
...
...
...
...
...
... OK, panic.

Probably a few but definitely not many, and those few are mainly going to be low-budget, low-profile games.