Since becoming Lead Designer of the world's biggest game (and yes, it doesn't really matter what metric you go by, that definition fits League of Legends), Greg Street has been front and centre for questions regarding the game. He's embraced that both through his own ask.fm channel and now a new Twitch series, running monthly, where a straight chat Q&A will be ran with him and Andy Belford, a member of the player interaction team.
Join the mass of humanity playing the best League of Legends champions for beginners.
It's interestingly open and unscripted, something you really don't see out of the owners of the largest multiplayer games in the world very often. You can watch the full archive in this video, starting from about 23 minutes in:
There's a lot in there for anyone interested in the game at any level, as well as plenty for those just after a bit of game design knowledge from those at the very top. Even as someone who only follows League passively and doesn't have nearly as much time in-game as anyone asking questions in that video, there's a lot of cool stuff in there. Plus, for those that are all-in, plenty of news and timeframes on various aspects of the game that are changing soon.
Riot will now be doing these every month with Street, for around an hour each time. He's also on Twitter, where he answers questions every so often, and his ask.fm is an almost constant feed of info. There's not a lot of announcements that way, obviously, but it's an open form of communication where almost anybody can get an answer on almost anything.