I don't actually understand what's so great about the Adventurer's Club. I want to like it, like, the concept, but it doesn't seem so great, from what I'm reading about it. I do have to admit that I've never been. But still...
When someone "bumps" a thread, they move it back to the top of the thread list (thereby increasing potential posts in their thread) by adding an irrelevant post, or "bump" to their thread.