I finally got an email about your reply. Maybe something is happening.
It looks like there's an issue with one of our email server whereby messages are getting queued up, causing a delay in notifications. We're looking into it, and hopefully it won't be too long before it's resolved.
For better or worse, you'll know it's resolved when you get a flood of notification emails that had gotten stuck in the queue -- I wish there were a way to modulate this flood, but unfortunately there really isn't much of a remedy given the nature of the current problem. Sorry for any inconvenience this might cause.