Google introduced a facial recognition feature for its Google+ social network. So far, it has been fairly well received--in stark contrast to a similar feature Facebook launched a few months ago. The main difference between the two? Google asked permission.
Both the Google+ and Facebook facial recognition features are designed to automate identifying people in photos to make it easier to tag them. Ostensibly, it will keep people more connected, drive interaction, and improve the social networking experience overall. That is, unless it is viewed as a creepy invasion of privacy.
Tacking an "opt-in" on features is like magic. It can take the creepy factor out of virtually anything, no matter how invasive it may seem, or how it might "infringe" on privacy. Once someone makes a choice to opt-in, they lose their right to complain about those things.
Opting in is the way real life works, and people generally expect to have some say in what they are buying into. If the guy at the ice cream shop just puts whipped cream, nuts, and a cherry on your sundae without asking, he's an overbearing jerk. If he asks if you would like whipped cream, nuts, and a cherry, though, he is providing added value that makes the ice cream experience more enjoyable.
The way Facebook approached facial recognition--and the way it approaches a lot of new features and capabilities when it launches them--is the equivalent of the ice cream shop guy just assuming, and proceeding to put the whipped cream, nuts, and cherry on your sundae, and leaving the burden on you to watch him like a hawk and "opt out" when he gets to that part.
Facial recognition is a cool feature, and it is quickly becoming more mainstream. My Microsoft Xbox 360 Kinect can recognize and automatically log me in. Google has included facial recognition as a means of unlocking Android "Ice Cream Sandwich" devices. Microsoft is rumored to be including facial recognition as a means of signing in to Windows 8 systems.
The cool factor, however, is easily overshadowed by the creepy factor when vendors just enable a feature like facial recognition. It is a little too Big Brother--too Minority Report.
I have said it before, I will say it again, and Google just proved it for me: privacy is not the issue, permission is. Users will gladly embrace and adopt features that infringe on their privacy as long as you put the ball in their court and let them surrender it willingly. If you take their privacy, there will be backlash.