Still, because so much facial information is available online at places like Facebook and Flickr, preventing that information from being used to intrude on individual privacy is almost impossible, according to Harry Lewis, a computer science professor at Harvard University. Lewis told PCWorld: "A private individual in a public--but what was previously thought of as anonymous--place is no longer going to find themselves anonymous."

People are quick to express concern about technologies like facial recognition in the hands of Big Brother, Lewis acknowledges. "But let's not get so worried about Big Brother that we forget about the fact that Little Brother is going to able to do exactly the same thing," he says.

Lewis also points out that, in principle, Big Brother can be controlled through regulation and legislation, but "we can't regulate what Little Brother does about public information, unless we want to surrender our civil rights of freedom of speech."

Some people argue, however, that anonymity began eroding long before facial recognition appeared on the scene. The proliferation of closed-circuit television cameras is an example of that trend. "The Big Brother thing is just technology catching up to what's always been there," says George Brostoff, founder and CEO of Sensible Vision in Covert, Michigan.