A Community Manager is a 
[Blizzard] employee that monitors the World of Warcraft forums, acting as a liaison between the players and the developers, along with other community-related responsibilities.
Community Managers should not be confused with the MVP (Most Valuable Poster) program, or with GMs (Game Masters)
US Forums
Current CMs
Past CMs
Moderators
EU Forums (English)
Current CMs
Other Blizzard Posters
Although not officially CMs, various other Blizzard employees post on the forums, including:
