League of Legends chat channels? Apparently, just shutting them down completely. Riot Games has removed several of the public chat rooms until the company finds a way to turn them into something "useful and accessible." The company is aware that there are great communities in the game, but it's too easy for toxic individuals to mask that.
Not only were the public chat channels problematic, but even the private channels lacked effective moderation tools outside of an ignore button. The development team is starting over from a new foundation, hoping to make the chat rooms a place to hang out with friends and more easily organize matches instead of being... well, what they were before. Feedback is welcome, so chime in on the official forums if you know what you want to see when the chats finally return.