Nikon cannot provide a serious competitor to the 5D MkII at the present time, with the D700 you have only 12MP and most landscape photographers will tell you this is simply not enough.
The D700 needs a battery grip to attain 8fps but this is in 12bit mode so not comparable to the 7D, but there are other strengths for FF & crop frame, control over depth of field, or the apparant extra reach crop frame gives.
Macro shooters for instance need lots of MP and good DoF a crop sensor is ideal just an example of why you can't have one camera which does it all. Perhaps the best of all worlds of the 1D MkIV with it;s 1.3x APS - H sensor?
All good points, and APS-H is a nice compromise, I love some of the shots i've seen from the 1DIV. However there are many successful landscape shooters using nikon D700 & D3 bodies. The difference in MP does not result in a dramatic difference in IQ between the 5DII & D700, I know people who shoot with both and IQ is a wash with a slight lead in high ISO performance going to the D700 and a slight lead in detail on very, very large prints going to the 5DII. Canon obviously wins in video. FF is obviously better for dof & crop gives you more reach with shorter lenses, essentially the difference between buying a 300mm vs 400mm lens, so they both have their uses.
I still contend that technology is such that a FF body can shoot 8-10 fps and that recently the performance limitation has been imposed by Canon to protect their flagship, not the availability of technology. EOS film cameras could shoot 10fps and those bodies had to advance a film roll so I know it's possible with digital.
My ideal body would be FF, 18-21MP, 1-series weather sealing, 8-10 fps, very clean ISO 6400 & dual card slots, the 7D AF would be more than acceptable on this body for me. I would imagine Canon could produces this body in the 3K-4K price range if they really wanted to do it.