Photo Tagger, now live, is another private alpha Facebook app using facial recognition, but this one was made with the avid photo uploader and tagger in mind. You can use the tool to scan Facebook photo albums for faces and tag your friends in bulk.
With the Photo Tagger application you can select from photo albums that belong to you or your friends, and use the app to scan the faces in each album. Once the scanning process is complete, Photo Tagger will return photos grouped by faces, some of which might already be identified by existing tags. You can then add a tag to a photo or a group of photos with the same face.
Once you're done, Photo Tagger will publish the tags and your friends will be notified accordingly. In demoing the app for myself, I noticed that even if you can't identify a friend in a photo, the act of bulk tagging someone else sets up a chain reaction where they go in and tag their friends, and so on and so forth. Depending on the size of your albums and the quantity of your friends, the tool could prove instrumental in your Facebook photo tagging process.