Do you ever notice while playing the game the option to "Like" a feature to get a cool item/perk/whatever? Or when you complete a mission, the option to tell a "friend" about your success?
A lot of Facebook games are using this strategy to help get the word out about the game using Facebook. Do you find these little options to be irritating or distracting? I personally have to stop at times while playing to read what it says so I don't accidentally broadcast that I just murdered a dog that was threatening the town to my entire news feed.