A rating system is really hard to build... and I don't know if it could work because nothing can me automated and all games should be checked.... so it's not possible.
Another point is that some game will be rated and some won't.. how to make the difference ? You just post it when you win ?!!
Well, the only way of rating players (fair and avoiding cheat) would be to create a championship were all matchs would be scheduled on the forum and also posted on it when played (like the current tournaments).
But for the moment, we don't even have a scipt to manage such championships.
Let's play tournaments, there will be soon plenty others (I'm waiting for purpose to open registrations). And later, when there will be more active players, we'll maybe think about championships.
All scripts to manage championships are welcome, just contact me.
The best defence is attack!