Call me frugal, but a D4 is not in my future. If I dropped $6K on a camera body I would also have to factor in the cost of the divorce! While the Specs at B&H show this to be a capable camera, especially the frame rate and ISO range. I just think $6K is just too much for a camera. I do not care about video and I am very happy with my D700. I note the D4 has a different size battery so you would need a new charger and new batteries as well. I am afraid the D700 replacement will be north of $3K also.