A Karma API?
sahaj: isn't this what "open social" is all about?  i mean you can't carry your karma (actually a pretty weird concept to me), but a person that chooses to associate with you, gets to see your profile, your friends, your pictures, and whatever other info you choose to share.  i think this model closely follows how real life works.  having a rating that describes and follows you, i think, is fairly useless (i'm sure plenty of you will disagree).