The best system so far would be IAR: http://iar.cs.unm.edu/ The email notices are pretty much on time and accurate. Problem is they have changed the system and I believe some forum page/link has gone lost that allows one to manage existing subscriptions as per: http://iar.cs.unm.edu/alerts.php#email
Correction: the page exists although difficult to find. As per Josh: "Once you login on the IAR forums, toward the top left of the page is a "user control panel" button. Click that and go to the "profile" tab. At the bottom of that page is a field: "user_ases".
-Hank
