Well, as your post count increases, your 'member status', as we'll put it, goes up. Here are the member rankings:
Newbie - 10 posts
Member - 50 posts
Advance Member - 100 posts
Melody - 1000 posts
Tune - 5000 posts
Rhythm - 10000 posts
Beat - 50000 posts
Symphony - 100000+ posts
Newbie - 10 posts
Member - 50 posts
Advance Member - 100 posts
Melody - 1000 posts
Tune - 5000 posts
Rhythm - 10000 posts
Beat - 50000 posts
Symphony - 100000+ posts