36Mp is very unlikely for a D700 replacement camera.
I doubt that Nikon will be looking to introduce a new model range to complement the Fx range, without first updating the current range.
D700 is now 3years old, and by comparison to the comp, is quite dated .. especially with no video mode.
IQ is still up and above what is considered acceptable .. so they really only need a few feature updates.
An 18 or 20Mp sensor, I can easily understand .. but 36Mp This is very unlikely in this level camera unless Nikon is phasing out the D3/D3x style of model differentiation.
We've never seen a tripling of pixel density in a single model line up ever .. from any manufacturer.
36Mp sounds plausible for a D3x replacement .. depending on what intel they're getting from Canon's moles(or maybe it's the other way around??) but one would safely bet that Nikon aren't going to be tampering with their model differentiation too much at this stage.
Anyhow, I wish they'd just hurry and bring out this new model FFS!
Then we can get on with the job of asking for and predicting impossible feature sets for the next model round up ... D900 .... 105 gigapixels, 2000 fps in raw mode, 1Tb buffer, native wireless capability ...etc, etc.