It is specifically the misuse or Hijacking of someone's Facebook page or "wall" for use as your own personal Twitter Page. All otherwise useless thoughts are posted to their page. You can regard their friends as "Followers", as they are exposed to all your minute by minute posts.
Guy 1: "My friend started twittering on my Facebook page, how annoying!"
Guy 2: "It's called fittering, you can do the same to his Blog (blittering) or linkedin (littering) page..."