To register for a forum account: log into SL, send an IM to 7Seas Sass, and tell her your email address. After about a day you'll get a forum password through email.
For discussion of all things 7Seas, user-to-user support, and fish or salvage trade requests. Any registered user can start new threads here and reply.
The ability to lock out replies on posts. Personal announcements and information don't require replies, and the poster should have the ability to lock the post.