When most of us went from 4 to 6MP to 10 to 12MP. There was a lot of talk of motion blur, and a lot of tripod upgrades. But we were focused on clean files at 100%. It seems likely that with the D800 handheld in low light downsizing will play a role - it simply wouldn't be reasonable to shoot for a clean file at 100%. I'll be interested to see how this plays out.