Do i see canon incorporating 4K into the next EOS camera 7D mkll or 5D mk4? Hell NO. All they'll do next is add things like auto focus to video, more unwanted ISO, 1080p/60p h.264, possibly wi-fi etc. If they ever add 4K,it will be so compressed so it doesn't compete with the 1Dc footage.
But thats just my opinion.
I personally would prefer 1080p RAW over 4k non-RAW
I think its high time we start looking to Blackmagic to answer our prayers for us