As reported on the official World of Warcraft Web site:

In keeping with Blizzard's aggressive stance against cheating in World of Warcraft, we have since patch 1.10 banned over 5,400 accounts and suspended 10,700 more for participating in activities that violate the game's Terms of Use, including using third-party programs to farm gold and items. Such actions can severely impact the economy of a realm and the overall game enjoyment for all players.

We will continue to aggressively monitor all World of Warcraft realms in order to protect the service and its players from the harmful effects of cheating. Please note that selling World of Warcraft content, such as gold, items, and characters, can result in a permanent ban of the involved accounts from World of Warcraft.

Many account closures come as the direct result of tips reported to our GMs in game or emailed to hacks@blizzard.com by legitimate World of Warcraft players. If you suspect that a World of Warcraft player is using an illegal third-party program to farm gold or items, or is otherwise violating our Terms of Use, please report the suspected infraction via one of the means listed above. All reports will be investigated, and those that prove false will not result in corrective action.

Thank you for your continued support, and good luck with your adventures in Azeroth!

-Blizzard Entertainment