I'm not sure one will appear to be honest, same with the supposed canon entry level FF camera also. The nikon one would have to be better than the D700, which isn't easy to do as its autofocus system is great, plus the iso performance isn't exactly lacking by any stretch. I'd rather see a new D300s with a higher mp count, better ISO performance and no AA filter, plus keeping the same framerate, as it would make it the best wildlife camera by a longshot for the money.
The second hand market for the D700 and the 5D mk ii has put the bodies to around £1100 each, which is an absolute bargain. I can't see how a new FF body, below the specs of the 5D mk iii and D800, would be able to compete with those sorts of prices.