Mine arrived yesterday. Nice heft and shape. After spending a while aligning its settings with my D90, I took it out as light was fading on a very gray afternoon for some dedicated high iso time. Shooting the ground, even at iso3200 I was forced (by the 24-85 lens) to shoot wide open at f4.2 and (by the light) at 1/50. The histogram still didn't crack 50%. Big surprise, though, in LR. There was a lot of really good information in those pixels and not a lot of noise. An exposure boost of 1 1/2 stops did not provoke an explosion of unmanageable noise. My impression is that the pixels were a lot cleaner than a D90 at iso3200 and it was far easier to clean up the luminance noise (virtually no chroma). Wow! Color me pleased.
BTW, new to me is the bracket burst available from the function button. This allows you to shoot the chosen bracket and only the bracket with one shutter press while still in single shot mode. I think this will be very useful.
I intend to keep using the D90 for walkabout (I depend on the reach of DX) but I know which camera will go with me to indoor events with 2.8 zooms. The D90 can continue to tag along with 1.8 (or better) primes.