I've owned just about every version of Photoshop Elements, the affordable version of Photoshop for the average guy. In version 8.0 they added a face recognition/identification that seems almost magical. It seems superior to the similar (and free) capabilities of Google's Picasa although I suspect they probably use some of the same technology.
The software can identify faces and "suggest" who it is. It's a bit unnerving to see it get confused about family members, it seems to sense the genetic connection. With this method I am able to apply keywords for family members, which is essential when looking through thousands of images.
I also took my first leap into the world of "professional" software when I got a version of Adobe's Lightroom (version 2). Since I was running Windows 7 (64 bit) I wanted to explore the capabilities of this wonderful product. I've started to just shoot in RAW mode and was interested with having more control over the images in the "darkroom" and wanted that to be in the 16 bit space.
Both products have their strengths and weaknesses. LightRoom runs as a native 64 bit application with no issues on my Windows 7 machine. Elements runs in the XP emulator space, with some hesitation. Why use both? Simple, the facial recognition software in Elements. After keywords are applied for People recognition, they can be written to the metadata for the file. Lightroom can take over and import those keywords for it's own database.
By using both products, it is possible to create a robust strategy of tagging your photo subjects. Have fun!