This is an example of it in action, but not sure how they did it:
http://mlb.mlb.com/photos/gigapan/?gpId=e9652024f103d4cd414e286ce041a419&c_id=tex

Basically I want people to be able to tag themselves and their facebook friends in photos on my website.  Surely it must be possible since they did it here.  Any ideas how this is done?
Thanks!