We’re transitioning to a proper Google Groups email list for various technical reasons. It should work essentially the same, with some convenient new features for you (like the ability to review a list of all prior messages) and less hassle for us.
Click here to sign up. Enter your Summoner Name as your display name, and click the “terms and conditions” checkbox. (Thanks to Seo Cypher for pointing that out.)
Note: Be sure to select the “send each message as it arrives” option. Google Groups is designed to accommodate forum-style email lists, so it has options such as “send me one email per 25 messages”. Since this is an announcement-style list restricted to a few messages per month, choosing that option would mean it would be over a year before you get a single email.
As always, we promise to limit email messages to no more than 3 messages per month. (That could change in future arcs, though not massively. In any event, one advantage of Google Groups is that you can easily unsubscribe anytime.)