Ok, I have had the D800 for a week. A bit of a learning curve but worth it. My standby macro lenses are too close and therefore have been difficult to use because of the shallow depth of field. What I have found was that I can get sharp macro shots from close-focusing wide angle lenses. My Sigma 10-20 DX works very well for macro. The tokina 11-16 - meh.
The autofocus for faces, pets, etc. seem to be dead on. No problems. Again, a learning curve.