Rumours have been flying around for a while. Thom Hogan’s logic about the life cycle of Nikon models and their launch times makes sense as is his question as to who will buy the D4 is also pertinent as it means that delivery will not be in the 100′s of thousands. The D800 (D700 replacement) and a successor to the D300s would be more important to Nikon. The only curve ball has been the Tsunami in Japan and the flooding in Malaysia which has set them back a few months. Expect an announcement at the PMA show in Las Vegas (January 10-13, 2012).
Here are a few specs gleaned from the web (scary right?) from sources that are generally on the ball. The D4 would be competing with the Canon EOS 1Dx.
16.2 MP (18Mp?)
Shutter durability up from 150,000 to 300,000 (A real guess)
100 to 102,400 native ISO range, expandable to 50 and 204,800
Face detection/recognition function that will work in the viewfinder (Nikon has submitted several viewfinder patents)
Improved video, possibly 1080p/30/25/24 fps and 720p/60/30/25/24 fps similar to the expected Nikon D800
Uncompressed video out through an HDMI port
Ability to assign the two front body buttons to smooth aperture control during video recording
Compatible with a new Nikon WT-5 wireless transmitter to replace the 2007 WT-4a
Ethernet integrated in camera (wired tethered shooting?)
Improved 51 AF points
AF detection range will go down to EV-2.0 (the D3s went to EV -1)
Autofocus system: 9 cross-type sensors operational up to f/8
Compact Flash + XQD memory card slots.
Gear I use: Bodies: Nikon D-SLR’s / Lenses: Nikon, Sigma, Tokina, Vivitar /
Filters: Hoya UV & Polarizing / Flash: Nikon Speed-lights / Bag: Lowe Pro /
Tripods & Heads: Manfrotto / Grips, Triggers, Timers, Batteries: Phottix /
Editing Plug-in: Topaz Labs for Noise Reduction, HDR.