The Members Area includes a forum to discuss tournaments, tactics, miniatures and more, and you can also spend many a happy hour in other forums.
Fumbbl has an extremely active forum for discussion of tactics and strategy applicable to tabletop play as well as the leagues and tournaments on Fumbbl. IRC chat is also available in various channels.
The main Cyanide forum is also very busy:
There are then forums to discuss Blood Bowl in various languages:
In addition, there are a few specific forums for particular countries: