A. a biased liberal who hates Bush, Fox News, and anything more politically conservative than that dirty, pot-smoking hippie who lives in the empty lot next your house
B. a saint (if you are said dirty hippie)
On a humorous note, Olbermann tends to call anyone who doesn't follow his political beliefs exactly (see: Communist Manifesto) The Worst Person In The World.
2. Someone who displays the traits of Olbermann, mainly being an obnoxious windbag who hates anyone who considers themselves conservative and doesn't even know much about politics.
Pete: Oh geez. It's Countdown With Keith Olbermann! Change the channel!
Pam: Nah, I'm keeping it on. I need a laugh.
2. (Takes place at an average American high school)
Jimmy: Dude! Did you see Pam start screaming at that quiet kid who was wearing a McCain button in the hallway? She just started shouting about how McCain was "The Worst Person In The World."
Johnny: I saw the whole thing. What was up with that? What did he ever do to her?
Jimmy: I know. She's such a Keith Olbermann.