Community Theater Green Room
   Discussion boards with topics including theater resources, articles, how-tos, directing, props, set design, play reading, and humor about acting.
   http://www.communitytheater.org/discuss/default.asp

Talk About Theater
   Theater discussion forums include a variety of topics.
   http://www.talkabouttheatre.com

Theatre VOICE
   Audio driven discussion forum in which theatre critics from across the UK press talk about London shows.
   http://www.theatrevoice.com