I don't like this newbie posting policy, whats the point
From what I can tell, two points:
1. It lowers the amount of spam that hits the forums.
2. It forces people to read at least a little bit before being released into the main forums. As most newbie questions have already been answered 10x over (if not more) it lowers the number of repeat questions on the site.
While you may find the 4 hour / 5 post requirement to be annoying it will make the remainder of the time you spend on the forum a more pleasant experience overall.