NikonRumors has some more details on the D800. A couple of things stand out:
"The D800/D800E will "read" images with 12 different channels (14-bit conversion)"
Does this imply off-sensor analogue-to-digital conversion, like the D700? The Sony column-parallel ADC technique uses thousands of "channels", so it can't be that (but that's what the D7000 uses). I'm not sure how the D4 works, but according to the Nikon brochure, it does have the ADCs built into the sensor.
The D3, D700, and D3S use six
Analog Devices AD9974 signal processors/ADCs on the main circuit board, which means the charge must be moved a significant distance while still in a noise-prone analogue state. This technique limits the engineering dynamic range to under 12 stops in these cameras, although their pixel architecture is capable of far more at base ISO. (The Analog Devices AD9974 chips also cost over $30 each, accounting for nearly $200 of the D700 production cost!)
"Start-up and shutter delay identical to the D4"
Good stuff. This will clearly be a very responsive camera, with the notable exception of the frame rate. You have to go back to the
D100 of 2002 to find a Nikon Dxxx with a slower frame rate! (Funny old quote from that link: "…the D100 is one of the fastest digital SLR's we've had the pleasure to test […] Remarkable considering the amount of data being shunted around the onboard circuitry.
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