If you post a lot on the board (or even if you don't), you may want to change your settings in your preferences. Something changed in its default settings, and if you do nothing, you'll get emailed every time someone posts a reply in every topic you've posted in. If you play games, that's going to be a LOT of emails. SO...to change it, you need to do two things:
1. Go to the top of the page and click "Profile". Then click "Preferences" and scroll down a ways until you see:
Always notify me of replies :
Sends an e-mail when someone replies to a topic you have posted in. This can be changed whenever you post.
That's auto-set at YES. Click NO, and you'll be good to go for future posts.
2. You'll need to go to any threads that you're already getting emails from, go to the bottom of the page, and on the right-hand side, you'll need to click "Stop watching for replies".
I don't know why the settings changed, but that could seriously clutter email in-boxes!