Here's the deal, at the moment Nikon has 4 digital full framed cameras and 2 sensors.
I do not believe, that the D700 will be replaced before the D3.
The simply reason being, they will probably use the same sensor. Nikon wouldn't want to release a smaller and cheaper flag-ship product due to loss sales on its larger and more expensive one.
What do you think am I talking non-sense?