D800: what's the point?

36M gives you plenty room for,

• Downsampling. Resize image from, say, 6000x4000 to 3000x2000, will improve its overall look, i.e. hide its fault.
• High Quality Cropping. At DX 1.5x or 4/3 2x crop, you'll get a 10-15M image without any quality loss.

And many others.