Those concerned about privacy with regards to Facebook will love this. If you try to block CEO Mark Zuckerberg on the site, Facebook won't let you. With most Facebook profiles, you can click "Report/Block this person" if you don't want them to be able to interact with you. Specifically, as Facebook says: If you block someone, they will not be able to find you in a Facebook search, see your profile, or interact with you through Facebook channels (such as Wall posts, Poke, etc.