There are two known bugs in the forum code.

1. The first time you go into your preferences to turn on email notifications, it doesn't work after you save. You need to go back and do it again. That will be fixed tomorrow with a new update.

2. Something is causing the email notifications to be turned off randomly. I've seen it twice. I can't reproduce. If you are able to figure out a pattern that cause the switch to be put back (or not save), please let me know.