I think the D800 is going to beat the D700 in every way but frame speed and I shoot at 4fps now so that will not effect me.
Improvements in focus speed, white balance accuracy, face detection, and active-D lighting will make up for having to use a higher shutter speed.
It will be great for capturing fine detail when there are a large number of people in the picture.
And more potential customers are asking me if I do Video at weddings.

But the ultimate camera will be the "low light" D4.

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