An announcement on the World of Warcraft forums says they've banned an unspecified number of accounts in World of Warcraft due to the use of bots, stressing their continued hard-line stance against cheating. Here's word:

We’ve recently taken action against a large number of World of Warcraft accounts that were found to be using third-party programs that automate gameplay, known as “bots.” We’re committed to providing an equal and fair playing field for everyone in World of Warcraft, and will continue to take action against those found in violation of our Terms of Use. Cheating of any form will not be tolerated.

If you believe that you’ve encountered a player abusing a bot, exploit, or cheat, please let us know! You can do so by using the right-click report functionality in the game, and/or by emailing information to hacks@blizzard.com.