Safe to say I favor greater pixel count in 95% of my still shooting settings - it just simply provides me with greater flexibility. For those with consistent low light or very low light needs this pixel density becomes a problem.

I am also old enough to remember the Olympus 1/2 from 35mm camera, am thinking the comparision might be for density might be viewed as turn the d800 vertical and either half would be roughly equivalent to a 18mp frame on the 7d-550 sensor - not sure of the precise dimensions but that would provide a 2x focal length conversion at the same pixel count.

I am a little surprised at the video side of the d800 if I understand it correctly. I do enjoy the 60fps on my plastic t31i and HDR rendering that it provides using Magic Lantern (get if you dont have it yet) - takes awhile for the computer to crunch through it - coffee break - I also like the 60 fps as 2 mp still (jack the shutter speed up) for the kiddo's soccer newsletters, etc.

I am looking forward to the Canon equivalent coming out - it really would be something if they put a stepped up HD resoltuion into the video capabilities similar to the 7.6mp capture in c300 - at 30/60 fps (lots o data & I am off my meds but it is only 2x for current density (4x data flow)

my 2 pennies.