See what Nikon Rumors have disclosed:
http://nikonrumors.com/2013/10/20/breaking-new-nikon-full-frame-hybrid-mirrorless-camera-coming-soon.aspx/
With brief rumoured specs as follows:
- Nikon FM2 like design
- Pentaxprism viewfinder
- 16.2MP 36x23,9 full frame sensor (same sensor as the D4's)
- SD memory card
- 2016-pixel RGB image sensor
- 9-cell framing grid display
- 3D color matrix metering II
- Native ISO range: 100-12,800 (incl. ISO 50 and ISO 108,200)
- 5.5 fps for up to 100 shots
- 3.2" LCD screen
- Battery:EN-EL14
- Dimensions: 143.5 x 110 x 66.5mm
- Weight: 765g
- It will come with a new AF-S Nikkor 50mm f/1.8G lens
Well, while this must be a really good camera I have to say, I am rather disappointed this idea was not first adopted by Pentax instead, which I made such a proposition back to 2008, for a retro-type DSLR of K1000D.