I know. I'm a shill for Google in just about any way possible.
And Picasa is a Google product that I use to manage all my photos at work and at home.
And yet, when I started playing around with the People feature and identifying a few faces, I wasn't particularly impressed. Yeah, I could go through my one-hundred-eighty-thousand faces one at a time. It would just take me forever.
Then I clicked a little lower to check out the individual on the list of names I'd been developing. By then, Picasa had begun using my identification to make reasonable guesses as to the other faces that I'd not yet defined.
And it was right like 90% of the time - which is pretty darn impressive.