in all fairness, you look just a little bit (nikonians, fredmiranda,etc) a used d700 is about $2000. I understand why it may not be what you want (size, price, no crop reach,etc). I recently went from a D90 to a D700. I also looked at a D7000. The D7000 had a lot of features that I liked over the D90 (lens focus Micro adjust, metal in the body, 2x card slots, etc), but I didn't really feel that the image quality was a big enough jump to justify the cost. I took some shots in the store with both the D7k, and the D700 and the D7k had that same high iso noise I was used to with the D90 and the D700, well, that was different. Much different. So I did a major lens reshuffle (I had a lot of DX glass) and went FX. This is also slightly motivated by the fact that I really liked the Nikon 50 1.4G, and on DX it is a very difficult focal length for me, whereas on FX, it is walkabout.
Anyway....I would really consider why you are upgrading and how much you will use the upgraded features of the D7k. It seems from the chatter that it is also a somewhat more difficult camera (harder on so-so glass,etc). I think the usual advice (and I know it is tough medicine) it to skip a generation of DSLR's. Now obviously that is up to discretion as the D3/D700 is miles ahead of the D2, but I think it applies for these fairly mature crop sensors.