[codebaobab]

"In normal privacy settings you can specific that either everyone can add you as a friend or only friends of friends."

There was a big privacy setting change last October that you could opt out of. So it is theoretically possible that he did. (I wish I had. I didn't understand the ramifications at the time.)

Obviously, if this is in fact the case, it is still a case of Zuckerberg not playing by the rules he is setting for everyone else.