I could see myself getting a D800 in a few years to make the move from DX to FX, but if I already had either a D7000 or a D700, I wouldn't feel inclined to upgrade to the 800 as the difference would be much less than from my 5000. That said, I plan on getting only FX lenses in the future unless there really is a convincing case for a specific DX lens. The 70-300VR is a great amateur zoom, and I'm looking at a 14-24 2.8 as well to stay with FX lenses.
It may be small, but I'm also not a big fan on the "sloping shoulders" of the newer Nikon models (3100, 5100, 7000, 800) over the older 90/3000/5000/300/700...
2016 GLE 350d - White on Black