Do not always think of an high end Camera.
I hope this Camera meets the D800, not the D4. Replacing the midlevel-series.
My Japanese girl-friend rumored, that Nikons replacement of their highend bodies will be a mixture of the d800 with the performance of the D4 with an superb low iso.
I am sorry, but Canon is 1 generation behind Nikon. If they would not have the dust-problem, I would switch too. A D600 would be great. Much cheaper then the 5D3, much better then the 6D.
And if they struggle to get back on the Camera-Olymp, I hope they do not see this as an chance of exponential rising of the prices.