I'm not sure what FX and DX bodies some of these folks are using, but I don't share their opinion.
I have a D700 and have shot the D50, D80, D200 and D300s.
In my opinion, the FX sense is superior over the DX sensor mint eh following areas: Dynamic Rnage is a couple of stops greater - very noticeable DOF is shallower and smother - lens and aperture being the same ISO performance is better due to the larger sensor vs pixel density
Let me caveat this with the fact that the D7000 has not been officially released and cannot be accurately compared, but I have studied Chase Jarves' images and video.
Also, I have a D7000 on pre order. Mostly for the video, but it is a great solid performer and will do fine as a backup to my D700 should i need it... But honestly, I really don't see how the quality of a DX sensor is going to match the FX... At least not yet.