I am very excited by the D3 for Nikon and myself (in the future, when I can afford one).
I think the opposite of “why?”
This camera has it all for the pro- especially the Photojournalist. It promises to be a low light camera with enough resolution for all of us who do not need 30x45 images daily.
12mp in FX mode. This gives the resolution needed for glossy photo mags like ESPN the magazine. I wonder if the stock agencies are going to up their resolution requirements to 12mp? Wouldn’t that hurt the 10mp MKIII guys! Wide angles will be accommodated without needing a 14mm lens. If you have the long glass to use with the FX sensor, then you can turn down the resolution for newspaper work and speed up PP if need be.
10mp crop mode to make file handling a little easier and bring more reach to your lenses. A 300 is still long enough.
5.1mp crop mode for more reach with still enough resolution for the newspaper sports guys. They can also use their DX wides.
In other words, the only people who need more pixels are
1. Those who’s clients require prints larger than 40x60 inches (medium format territory).
2. The ones that just have to have more pixels because they need them to feel like a man.
3. Won’t or can’t hike with larger, heavier lenses, won’t use a TC or the DX crop because it doesn’t have enough pixels.
That means not many people. Flame away.

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Chris, Broussard, LA