Help! Stopped Receiving Notifications!

Today I very suddenly stopped receiving notifications regarding forum posts. I happened to be looking at a thread I had commented on this morning and noticed someone had responded (without my getting a notification), voted up one of my comments (without getting a notification), and added additional comments to the thread (I am subscribed to the thread, so I should have received a notification). I have no idea if this is localized to this one thread (found here) or if I have stopped receiving ANY notifications. I am very active in my subcommunity forums and would hate to miss out on a good conversation because I was unaware of any relavent activity.

I don't know where to submit a tech support ticket - I had the link once, but not anymore. Hopefully this is fine. Though I may not know if anyone ever responds to this thread if the notifications aren't working...