According to latest rumors (Mirrorlessrumors.com) Nikon will use Sony manufactored sensors to launch a complete new and pro mirrorless system. There is a fair chance Nikon mirrorless camera will feature the same 24 Mega-pixel sensor that will be used inside the upcoming Sony NEX-7. The bad news is that Nikon will present their camera in April and the Sony NEX-7 should be announced a few months after
A part from the Sensor Sony and Nikon will NOT share the same E-mount. Nikon will go their own way. To bad, I would have loved to see a partnership on the same system like the one between Panasonic and Olympus.