I likewise came from a D700, so completely happy with the move up to D4. I'm doing a lot of video too. I am one of those who thought perhaps Thom had some major concerns, given his longish silence and occasional blog gripe, but I see he pretty much likes the D4.
I also appreciated his comments on the so-called "soft" full-frame format video. I use the 70-200 a lot on my D4 for video and because 70 is not all that wide in 2.7-crop, I end up shooting full-frame video a lot rather than my preferred CX-mode video (which is truly stellar). As an aside, there was a recent patent for a 50-300 f/2.8-4 lens and for video this would be ideal as it would allow me to pretty much always use CX-mode video on my D4.
Looking around my camera a bit prompted by the review, I ended up making use of the (f7) vertical grip fn button (AF-Lock, and +- EV Comp) whereas before I was making zero use of this button, so I'm happy there. I also ended up changing f6 centre sub-selector to toggle me back and forth from 8x10 mode which I use for headshots, so again happy to make more use of programmability.
I am still completely frustrated by the implication of f5/f14. I would like to make differential use of the sub-selector and multi-selector left-right-up-down buttons but be darned if I see how the camera allows me to change the function of the multi-selector left-right-up-down buttons! Would sure appreciate if anyone has advice as I DON'T GET IT