Any MMORPG player knows that there are some people who can't help but abuse the game's chat system, giving proof once again that we just can't have nice things.
Blizzard knows this firsthand with World of Warcraft, which is why it has unveiled a new punishment upon chatty asshats and spam accounts with what is dubbed "The Silence Penalty."
Any player who has received multiple "Spam" or "Abusive Chat" reports will be investigated by Blizzard (it won't be automated as that can lead to abuse). If Blizzard does find abuse, the player will receive the silence penalty.
While the penalty will still allow the player to whisper, enter raid chat, and talk in Global Channels that have a moderator, the player will not be able to talk in instance chat, talk in auto-joined global channels, or send anything from party invitations to duels. The first instance of the penalty will last 24 hours but each subsequent penalty will double it… and will continue until infinity. (That's a long time.)
The penalty will be a part of the game once the pre-Legion patch arrives, which you can pre-load right now. It will likely come next on July 19th, after the PvP Season 3 finishes.