That there is a link on the right-hand side of the forums to subscribe to specific forums?  Here, I'll give it to you again.  =)

Now if you click on the link, you can get to a dialog where you can subscribe to your favorite forums.  That way, when somebody posts something on the forum, you get an email with the text of what they said.

We're working on getting the reverse working (send an email and it ends up on the forum), but it's been beating us up trying to get it going.