Hi all,
Actualy, no
I have read somewhere (if talking about phones), that at 5inch humans eye can't see already the real the difference between 710P and 1080P. So it may be actual only for big TV's. But there is nothing to watch. Blu Ray is max 1080P and I have only 3 HD channels on my TV available, so no big rush 
I agree with Alan. When comparing a 720p phone to a 1080p phone, I can immediately see the difference.

Sometimes I can see the little curve dots that make up the icons, even if they're really tiny, on my HTC One (468 pixels per inch).
As we own a family "TV", but don't pay for television service, I do not know how newer shows look as of now, but these 2160p tvs should feature better up-scaling, or so I've heard. Although not the prettiest alternative to watching a lower-res original, it could get the job done..
The 16:10 equivalent of 2160p should be 2400p afaik. As I (really, really) loved my 16:10 (1440x900) monitor (and I was quite surprised as to how different 16:9 was), I am greatly considering a 3840x2400 monitor once the price goes down. Preferably < 40 inches for usability and to preserve the ppi ratio, even if it's still low compared to phone standards. As Pondus showed, 8k should allow bigger monitors/tvs to have an even higher ppi.
The monitor would allow me to handle bigger designs with ease. Since 4 1080p displays can fit into one 2160p display, we could also see a new program that allocates 4 virtual desktops on one screen.
I'm not sure about watching television on a big 2160p screen just yet, but it will come in the future. Modern consumers may not think about a 2160p display until 2015/2016/2017? But regardless, this means that the expensive now will become more affordable in the future!
Toshiba has already announced some 2160p laptops for Fall 2014. Could this be the start of 1080p laptops becoming standard? Won't the already-existing 1440p laptops become cheaper?
And: Regarding the flexible 4k displays... when will we have a
touchscreen flexible 4k display? Or is there already a prototype?

~!Donovan