D800 Face Detection in Viewfinder

The D600 does support Auto-area AF as well!

D600 manual page 99 quote:

Auto-area AF: The camera automatically detects the subject and selects the focus point. If a type G or D lens is used (0287), the camera can distinguish human subjects from the background for improved subject detection. The active focus points are highlighted briefly after the camera focuses; in AF-C mode or when continuous-servo autofocus is selected in AF-A mode, the main focus point remains highlighted after the other focus points have turned off.

Auto-area AF was also already available in camera's like the D300 and D700, but I've rarely used it. In my D800 I've tried it once and it seemed to work OK.

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Jur