"Advisory says that logging software may have stolen some users' passcodes."
Twitch, the Amazon-owned game video streaming service, has reset passwords for all its users after warning of a security breach that may have allowed hackers to access user names, passwords, and other personal information.
According to a blog post Twitch published Monday evening, current passwords have been expired and users will be required to create a new one the next time they log in. Accounts have also been disconnected from Twitter and YouTube. As is standard practice, anyone who used the same password for multiple services should assume it's compromised and create a new and unique passcode for each property. Credit card data was not affected, the company said.
Continued : http://arstechnica.com/security/2015/03/twitch-resets-user-passwords-following-breach/
Related:
Twitch Hacked
Twitch forces users to reset password in wake of breach
Post-hack, Twitch users told to reset passwords.. but they don't have to make them too long
Twitch resets passwords, says user details may have been stolen

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic