The new forum software gives the ability for individuals on the forum to create and manage clubs. My impression is clubs are a by-invitation area that members can establish that allow secluded topics and discussions on the forums. Kind of like the way we have use group messages in the past. However, there is also functionality for paid memberships and separate galleries and calendars, so it may lend itself to car membership clubs and similar.
I setup this 'Lifetime Supporter' club so enable me to play with the functionality.