TAT (The Astonishing Tribe) has done a prototype of Augment Reality ID concept. It uses Polar Rose Facelib software to recognize faces and added social networking information onto the person. So, when you point your camera phone to a person, the software will try to recognize the face. You will need to join Recognizer service to upload your pictures to get recognized. Video after the break.
This method of opting in the service is good. It does not intrude your information. You are the one that control the information to be shown to people. BTW, the demo is done on an Android phone.
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