According to Nikonrumors there will be two mirrorless cameras form Nikon (the V1 and the J1). The only difference between the two is that one has a self timer :)
Those are the specs:
10.1MP
ISO range: 100-3200 (with H1-6400)
CCD sensor (not sure about that) – the whole mirrorless line will be called CX, similar to DX and FX
phase and contrast AF detection
Both cameras will have 2.7x crop factor
3 in. LCD screen
The J1 model will have a built-in flash
The V1 will not have a built-in flash but it will have a multi-accessory port which will support external flash and a GPS device
There will be no traditional flash hot shoe on both models
There will be a F-mount adapter
Both cameras will probably be made of plastic
Full HD movie with many additional features
EXPEED 3 processor with 600 megapixels per second processing power
The four mirrorless lenses are (most with choice of colors, except the 10-100mm):
10mm f/2.8 pancake lens
10-30mm f/3.5-5.6 VR lens (very short and portable)
10-100mm f/4.5-5.6 VR
30-110mm VR