Me and some other people have mentioned this on various threads in the past. The email notifications seem to be intermittantly broken. Sometimes notifciations dont send at all and sometimes they take days
The problem, unfortunately, is I have no idea why this is, and don't even know where to start looking to debug. The email settings for my server are correct, emails seem to be getting through everyday ... perhaps you have visited the forum since the thread was replied to, and so a notification isn't necessary?