The Nikon D3S now has 5 settings for Active D-Lighting. Low, Normal, High, Extra high and Auto. This image compares D-Lighting setting Off and thew new Auto setting. The extra detail in the blown highlight area is obvious.
I usually turn this off when shooting sport as it tends to bog down the capture speed. It was slow in the D3 and it seems its the same of the D3S. If you’re not sure what Active D-Lighting does Ken Rockwell’s got an explanation.