Use Faces in iPhoto
12 Days of Geek Tips: Organize iPhoto By Faces
Break out the 32GB SD card, because December's festivities call for a whole lot of picture-taking. Make sure to do one thing for me, though — actually transfer those photos from card to computer. Apple's iPhoto for desktop ($15) and iOS ($5) makes organizing photos and albums a nearly effortless endeavor. In fact, you can use the software's facial recognition technology to categorize pictures by person.
Upon opening, iPhoto will automatically search for new faces and categorizes them in the folder marked Faces in the Library. Open the Faces folder to see images of people iPhoto wants you to name. Begin categorizing loved ones by name, and those people will appear on the Faces cork board. Once you've named several photos, iPhoto will start to suggest prompts for unnamed faces. Go ahead and click the checkmark below a photo to confirm the name, or the X to reject it.
Email addresses can even be included in a person's Faces tag, making for a streamlined export to Facebook that includes your friend's tag in the social network.