well, i think what i'm going to do is bide my time. excited to move to the nikon system but i think it'll go bit by bit over the course of a year.
sounds and looks like you know what you are doing
as far as the raw files looking different, yes, the 5d and 5d2 images are wildly different when it comes to how they react to black point, contrast and fill sliders in LR. the colors are also significantly different, with the 5d2 being far more magenta despite infinite fiddling with HSL sliders and camera profiles.
i doubt you'll have this issue with the d700. i only worry about colour casts when going to print.