D800 36mp bonkers!
Let me say straight off, I'm not a Nikon user, but I often pop along to this forum to check out the D700/D3 images. Why? because I believe they have superior IQ to all others.
Those 'meager' 12mp produced beautifully clean files. No amount of EXPEED jiggery-pokery will allow the new 36mp sensor to emulate this.
Please hang on to your D700's for a little longer, at least until you are damn sure 36mp wasn't just marketing.