We do not have such a system implemented in our forums. Other forums, like SPPf have a system where if you "recruit" other members to join their forums, you get special privilages. The reason why we don't have it is probably because it is we want all of our members to feel equal. I could also see how it could create a spam problem, where people spam in other forums or by e-mail so that they can get more points.
This doesn't mean that the system is wrong, though. It may be more suitable for different types of forums.