, "In the 2000 presidential election, the Mexican government employed facial recognition software to prevent voter fraud. Some individuals had been registering to vote under several different names, in an attempt to place multiple votes. By comparing new facial images to those already in the voter database, authorities were able to reduce duplicate registrations. Similar technologies are being used in the United States to prevent people from obtaining fake identification cards and driver’s licenses."
So yes, governments are using this; do you think this is a good thing considering the many abuses of power we've seen in the past few months with regard to the protests?
Germany is about to ban this sort of technology: http://blogs.wsj.com/tech-europe/2011/11/11/german-authority-could-sue-facebook-over-facial-recognition/
"The state data protection body in Hamburg, Germany, appears to have lost patience with Facebook. It had been in conversation with the social network over its use of technology that automatically recognizes and tags users’ faces at a click using a biometric database."
The EU just came down hard on EULAs, like the one Facebook uses. G+ is setting itself up for some serious legal challenges in the future with regards to civil liberties, whether it's opt in or not.