The software follows the user, or at least the user insofar as they interact with it. I just sit here and marvel. Actually, I don't, because I'm not following anyone, but I marvel at other things. I don't really understand following, because it's not as though the forum is so large that you're likely to miss anything. I suppose it's a way to get hold of people's posts before they've been neurotically edited and blackmail them about it later, if you didn't happen to have been around to catch it at the time.