Facebook adds face detection for photos, only 1% of users have it so far
It doesn't sound like this is full-on facial recognition and auto-tagging ... yet. That seems like the obvious next step for Facebook, though. If they go that route, they'll already have the ability to pick a face out of a photo, and then plenty of user data about who the faces belong to. Geez, it's hard enough to untag my ugly mug in photos as it is!
If you don't see face detection on your photos yet, don't worry. Only 1% of users have it so far, according to Facebook.