A true D700 successor: D600 sensor in D800 body ... and fur gods sake, leave the damn video out!!!

Compete against 5D3 really?? Put D800 in 1.2 crop mode it shoots 5 fps at 24 meg. One frame a sec less. When shooting fast frame rate your generally shoot some kind of action with a longer lens so 1.2 crop mode no problem. Its not like you put a 16-35 lens on and shoot a 5 fps. You have way more pixel reach than 5D3 with d800. Not really seeing its downside. Put it back to FF for wide angle you have 36 meg to measly 22 from 5D3. 5D3 does NOT have better high iso, just smeared jpg's do from 5D3.

Now Nikon might do a D400 and that should do 8fps so maybe thats what you want, a cheaper D4 plus no built in grip. So sure Nikon could do what you want but highly doubtful. D800 close enough to what you want.

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