Stack Overflow opened its doors yesterday after a closed beta test period of 6 weeks or so. At first glance, it’s a programming support forum, but it has interesting mechanisms to ensure the signal-to-noise ratio is high.

Borrowing from the idea of XBox360 achievement points, Stack Overflow awards its registered users “badges” for partipating in the site and exploring its features. Some badges are easily won, such as “Autobiographer” for completing your profile. Others might take some time, such as “Necromancer”, for successfully resurrecting a year old question with a popular answer!

Added to that is a system of karma, or reputation, where your contributions to the site are voted on. If someone likes one of your answers, or thinks you asked a good question, they can vote you up, giving you more reputation points. If your answer is the preferred answer to a question, you get even more. It works both ways, if you post something dumb or irrelevant, it will get voted down, lowering your reputation .

The key thing is that your reputation level influences which site features you have access to. It gradually exposes more moderation features to you as you contribute more to the site. For example, earn 2000 reputation points and you get the ability to edit and delete other people’s posts.

If it works, the site will practically run itself, but it will be interesting to see how much people try to game it and abuse additional privileges. Some of these ideas might even be applicable to how Geograph’s moderation system works, so it is doubly interesting to me.

Anyway, if you have a programming question, give it a try. Most questions seem to get answered withing a few minutes, and it certainly beats Googling and getting one of those paywalled Experts Exchanges pages!