Tom Raftery’s I.T. Views points us towards Riya. He describes it as:

Riya, formerly known as Ojos, is facial recognition software - basically, if you upload you photos to Riya, it will ask you the names of people in the photos, and quickly start to recognise them in more of your pictures so you get a searchable index of all your photos of people.

Sounds excellent. Read his full post. He points to the first review of the software and the official site’s learn more which also gives you a bit more insight into what’s going on.