It might be more fair to say that the 1,8 35mm DX lens compares to the 50mm 1,4 lens as they carry a more similar equivalent focus on the two cameras. The 35 equating to a 50 in FX terms. The 40 1,4 is usually around 400$ and sometimes less (depending on what country you live in) so the difference is 'only' double.
The D7000 has me really really salivating as I have a very used D200 that I'd like to upgrade. Thankfully, I have no money, so that isn't an issue that'll keep me up at night, at least not for the short term. What I prefer about FX is that the wide angles are really really wide. When I used my 24-70G lens on a borrowed D700, I was surprised at how much wider the frames were. That is probably the biggest draw for me. Of course, if I was a birder, the DX would be my first choice as I'd be getting an extra 50% focal distance from the same lenses and that alone saves a lotta dosh.
They are in 2 totally different classes, but clearly have some similarities.
The shutter mechanisms are both tested to 150k.
The high ISO shots by Chase Jarvis for the D7000 are pretty clean, but still behind the D700 to my eyes. . .
One is DX and the other is FX. . .very different effect on framing. 100% VF for D7k and 95% for D700, another significant difference
The price different is pretty significant too - $1000. NOT including the fact that FX lenses are more $$$ than DX (35 1.5 FX is $1800; 35 1.8 DX is $200).
So net net, D7k is more of a DX backup to the D700.