Currently you only get a single email notification when anyone posts to a conversation you are following, then no further email notifications no matter how many posts are made. You have to log onto the forum and view the new posts to "reset it". Then you will get another one-time-only email whenever someone posts to that conversation again.
This has been discussed before, and some people like it this way, but others do not (including myself). So I am requesting a feature to add a setting that controls this behavior, letting you choose whether to get individual emails for each post or not.
Again, this is only for conversations that I am following, not channel follows.