Definitely not disagreeing, i think that would accommodate a lot more peoples needs then a 24 mp 4k camera can.
What i am coming at though is trying to look at it professionally (ie Dan Carr)
I have seen a lot of his work and it seems that he is doing very well photographically, but also getting into the video industry a little bit more. Seems that with his new 5d iii and possibly working with a RED here and there, that maybe some professional photographers are getting more into the video world that comes with their high end digital slr.
I don't think 4k is really the answer there, but I think high end video and high end photography can go well together with the right specs/price point
my .02