I have a D3 since november 29th and I'm very happy with that choise. Next to the fact that this camera's high iso performance is more a revolution than an evolution there are others things that matter while using this fantastic camera.

After several tests and with my first 35mm sensor DSRL experience -Canon 5D-, I learned that bigger sensors (with larger pixels) are much more forgiving with prosumer or even mediocre quality lenses than DX cameras with little pixels and high pixel density. A little bit logical if you imagine how precise a lens has to be made to transfer light rays to a tiny little sensor with 10 million or more photosites on it... 
Next to that larger pixels often create more opportunities for higher IQ and lower noise  than little pixels, and while you need more space to pack 10 or 12 million larger pixels on one sensor than 10 or 12M little pixels, bigger sensors with low pixel density mostly give better IQ and lower noise opportunities than smaller sensors with higher pixel density. If pixel density gets really too high, this often results in much more noise, lower IQ and more undesirable artifacts. There is an interesting article about that from Vincent Bockaert in the Dpreview glossary which states that: "...A 6 megapixel digital compact image will be of lower quality than a 6 megapixel digital SLR image with larger pixels."

As I like to have a walk-around lens on my camera that covers a nice focal range I purchased the Nikkor 28-105 3.5-4.5 and the Nikkor 24-120VR and did a sharpness comparison test against expensive pro lenses and some primes. The test is basically made for my own use and helps me to decide what lens I want to keep for common use on my D3 and also not to let me influence anymore by sometimes extreme different opinions from other users on photographic gear website's forums. So called "lens flaws" reported by amateur users are more than often users mistakes...

This test has been done on tripod, all in 3 different apertures and @ 3 focal lenghts: 28mm, 50mm and 105mm. The camera was set to "normal" sharpness in the in-camera settings , all shot in JPEG, and exposure delay mode "on". None of this images have been postprocessed for sharpness or whatever, only resized for website publication. Colours and saturation could be pushed in PP as well, but I wanted to have "neutral" pictures.
Of course the original sized pictures for the 50 and 105mm samples would show more detail, but then they would be too big to suit on the layout of this website.