Sites for movies, television, radio, videos, programming guides/tools, comics, performing arts, museums, art galleries, or libraries. Includes sites for entertainment, celebrity and industry news.
As compared to Blue Coat's description for it's "Entertainment" category:
"Sites that provide information about or promote popular culture including but not limited to film, film critiques and discussions, film trailers, box office, television, home entertainment, music, comics, graphic novels, literary news, and reviews. This category also includes entertainment-oriented periodicals, interviews, fan clubs, celebrity gossip, and podcasts; and music and film charts."
Honestly I've never seen a URL filter that bothers with a seperate "Music" category. Our firewall team has the mistaken impression that it's for streaming music which has upset some users.