The Japanese magazine CAPA published drawings of Nikon D4 and D900 cameras. They have posted similar drawings of non-existing Nikon DSLR models in the past. My understanding is that those drawings are based on input from people in the industry.
Nikon D4:
- full frame 18MP CMOS sensor (8 MP when cropped to APS-C)
- usable ISO 51200
- 11fps (20fps with live view, 30fps with APS-C crop)
- flexible LCD monitor
- built-in WiFi
- 51 point all-cross AF point
and the Nikon D900:
- full frame 18mp CMOS sensor
- usable ISO 51200
- 8fps, 10fps with grip
- 4″ LCD screen
- dual SDHC slot