I'm not as sure as you about the immediate death of DSLRs for filmmaking. I think lots of people (me amongst them) will still use them for quite a time.
I know you have to make your own decisions, but I'm hesitating whether I should make a brand switch and I would like to get your opinion as well as the forum member's.
I own and shoot with a Nikon D800 and 6 different lenses (Nikkor, Tamron and Samyang). I'm a little disappointed with moire issues and high ISO performance. But, above all, I feel Nikon never had a real intention to compete in the video league, just as you mentioned. Canon has always been several steps ahead. More over, Canon users have the chance to use their lenses with photo cameras (MkIII, MkII, and so on) as well as cinema cameras (C100, C300, etc.).
Regarding still photos, I'm very happy with my D800.
This week I had the chance to play a little with a 5D Mark III. I loved the ergonomics, the back LCD, lack of moire, high ISO performance, ease of use of menus, plus the possibiliy of installing Magic Lantern with all its features.
Would you make the switch from a D800 to a MkIII?
Would you wait to see the market trends?
If I make the move, it is not just to buy a Canon 5d Mark III instead of a D800, but with the intention of joining a brand that seems to integrate photo and cinema lines much better than Nikon.
Thank you in advance.