Noun: A person who is frequently on facebook's newsfeed.
Whenever you sign on and look at the newsfeed to see what your friends have been up to, you can't find out because the ONE person takes it all up with their recent boring activity.
me: "Let me sign onto facebook and see what everyone has been up to!"
1 minute later
me: "well... it looks like Sarah has been posting quite a few videos lately.."
Cletus: "ya, she's such a newsfeed whore"