in my ecosystem, the display resolution and the source resolution have already totally split(well, sorta. i haven't technically moved on from 1080p in any form yet)
but, while 8k displays may be available, and 4k displays are now affordable and common, there is ZERO UHD sources available to me now or in the foreseeable future other than discs. this means no netflix, no cable, not even illegal streaming because the bandwidth coming into my home can't support it.
what this means for ME is that, displays need to be super good at upscaling, and they need to show an advantage without native content. for right now, i consider my 1080p tvs 'perfect' resolution, only the projector still has visible pixels(if i'm being super picky). not to say i would avoid 8k tv's, just that i'm not going to trade in my 1080p displays for 8k ones anymore than i would toss out a 100w per channel avr for a 150w per channel one. at this point, it's truly 'just a number' to me. it will be the other features and improvements that will get me to upgrade, eventually
Displays: Samsung PN64F8500/JVC X35
AVR: Pioneer VSX-1130K, 7.1/5.1.2 audio
Sources: HTPC, PS3, XBOX360, Wii
Control: Harmony One