UHD will not be coming any time soon. I know from where I speak. I edited a 4k movie and we've had so many problems just getting it shown at that resolution.
That's 4096x2048, forgetting just the bandwidth necessary to carry that much data, and the cost of even owning a set capable of displaying that, movie production companies are not even ready for this stuff, TV stations are still trying to justify costs for HD conversion.... so as far as UHD goes.... well... my kids may be complaining about that one in 20 years.
If you're interested in 4k cinema, check out our website. Postcards From The Future
4k is being installed in some movie theaters: http://news.sel.sony.com/en/press_room/b2b/broadcast_production/release/31919.html