This much is completely public: http://www.apple.com/ios/ios6/#facebook http://www.apple.com/ios/ios6/#facebook (Click the "Contacts and calendars", and see t

This much is completely public: http://www.apple.com/ios/ios6/#facebook http://www.apple.com/ios/ios6/#facebook (Click the "Contacts and calendars", and see that contacts can have multiple addresses, even with Facebook sync.)