Twitch is saying admin account was compromised via social engineering, I suspect that means a Spear Phishing attack http://us.norton.com/spear-phishing-scam-not-sport/article
Sounds like Day9, Athene, among others can't even log in according to link above.
Snippet from link above:
At this point most of these have been already fixed. Twitch.TV is reacting as fast as they can and are unbanning streamers. - 3:32 p.m. ESTIf you know of any other hacks, let us know here or tweet at us @GAMEBREAKER.TV and/or use #gbtips.