4K channels we know have turned up, in the US & Eu
Post# of 96879
SES (Satellite Owner has touted) they have 19 4k channels up on satellites they own, that was end of 2015.
we have seen other European broadcasters say they are or have launched 4k channels.
Direct TV/AT&T saying they will have 19 4k channels by middle of 2016.
Asia Region has 4 channels that *I* know of and a lot in the wings.
Then you have all the VOD from Ultraflix, Netflix, Amazon, MGO, Youtube, ect...
I also think content was held back due to the uncertainty of where HDR was moving & VR and standards/compatibles..