I really want to move away from my D7000, but there's no evidence as yet to support the D800 as suitable for one of my important genres of photography, wildlife. As I've stated elsewhere until I see some high ISO large crop images I can't make a decision. To be frank I don't know how anyone in my situation could.
As Nikon state that any ISO noise on the D800 will compare to the D700 I am pleased. In fact I have just taken some images today of a test target using a tripod and a 300mm f4 lens with my D700 in both FX and DX mode and then in DX mode with a x1.4TC. All were taken at IS01000 The results are very promising and I am pleased.
If samples appear taken with the D800 that replicate at the very least the same IQ, then I can allow myself to consider owning a D800 seriously. I am positive, just like I am with my D700, that the D800 will satisfy all of my landscape, portrait and architectural needs then I can progress. If not, then I'll wait for the D300s replacement.