The first underwater housing prototypes for Nikon D800 and D4 cameras are already out and they look slick. I was told that the Hugyfot housing for D800 will cost “only” €2,850 including VAT (around $3,700). Hugyfot showed also those 3D rendering for the D4 housing at the London Dive Show:
Nauticam already has a working prototype of an underwater housing for Nikon D4:
Via Wetpixel