The true genius of the D800 was the D800E. I would gladly take an 22Mpx 5dmkIII. But I want to be able to have no anti alias filter. It makes a world of difference for sharpness, and it wouldn't hurt the sort of photography that the 5D shooters usually do. In any case, you could always buy it with the AA filter.
On the other hand, when pixel peeping the D3s and the D4, I find the high iso setting have lots of noise reduction and correspondingly very little sharpness. It's clear that the 1Dx has better underlying noise characteristics. So I hope to get that quality in the 5DmkIII, I don't care how many pixels.
What would be awesome is if they could somehow enable or disable the AA filter via a menu setting.