About the picture quality the previous speakers have already written a lot, and in [...] are also quite a few images taken with the D800 in the net.
What I also like that the camera with a SanDisk Eye-Fi Secure Digital High Capacity Card (SDHC) + Reader 4GB works well in direct mode, so that a picture control on a notebook or iPad without cable and without problems is possible ( even tested). While the data transfer takes a little, but that's due to the file size so no Wunder.Man can yes the Raw files (making it the faster transmission) on a CF card and JPEG in reduzeirter quality / resolution can write to the SD card.
My D700 (now as a second camera) I'm still going to keep because of the faster frame rate for shooting sports.