A while ago, some posters mentioned that it would be good if LW had a forum. Earlier this week I was planning a role-playing game with some other users and decided that a forum would be a good place for us and other groups to play online. And the Less Wrong Forum was born.
Currently, the forum has three boards: Gaming, Less Wrong/SIAI Related Topics, and General/Meta. The Gaming board is for RPGs, Diplomacy, Zendo, or any other games rationalists might enjoy playing together. The LW/SIAI board is for discussing any of the topics we normally discuss on Less Wrong. The General/Meta board is for random topics and discussions of the LW site or the forum itself.
EDIT: Looks like a supermajority of commenters don't want the LW board to exist because it would be redundant with the discussion section. I'll leave it up for a bit longer, and take it down if nobody says they support it.
I encourage everyone to check out the forum and help make it a fun and useful part of the online rationalist community. Please make suggestions in the comments (or on the forum itself!) about how it can be improved.
EDIT: Due to problems with trolls, registration now requires an invite. If you want an account, say so in the comments and I or the other admin (Armok_GoB) will get you one.
Seconding the dedication of the forum to gaming. As mentioned elsewhere in this thread, a flood of gaming-only posts is something worth avoiding.
But I wonder if the /r/LessWrong on reddit would do. Subreddits seem nicer to me compared to the kind of shoddy proboards forum.