Due to popular demand, forums were added to the panel of MusicBrainz communication means in 2006, initially as to satisfy the needs of people who don't feel at ease with mailing lists.
You can access the forums here: http://forums.musicbrainz.org
Actually, our forums cover the following topics, broken in two sections:
Pretty much, its use duplicates the Users Mailing List (in a more declined way), and to some extent the wiki.
It was suggested in the past that we rationalize these as to keep things more clear (and possibly discontinue what's redundant), but in the end it reached some sort of natural balance: a number of users seem to appreciate the forums, essentially for routine questions (indeed partly superseding the Users Mailing List), while more involved people keep using the wiki and specialized Mailing Lists for advanced discussions.