To be extremely, extremely excited or agitated.
With his fiery oration, Goldberg worked up the angry mob up to a fever pitch.
Fever Pitch (1996) is also the name of a book by Nick Hornby (High Fidelity, About a Boy). It chronicles Hornby's obsession with the English soccer team Arsenal and his recovery from that addiction. It makes an interesting tandem with Bill Buford's book, Among the Thugs (1993, about football hooliganism.) I believe that it was made into a movie.