This was posted on the official Blizzard Website:

The Latin American Spanish version of World of Warcraft is gearing up for release and will be available for purchase starting next Friday, July 25. See the press release and FAQ for further details.

To celebrate the release, we’ll be holding a launch event in Plaza Satelite, a mall located in Estado de Mexico, on July 26 and 27. We’ll have activities to participate in and prizes to win, and you’ll be able to meet members of our Latin American team and other Blizzard Entertainment employees. For more details, please visit the event webpage.

If you’re new to World of Warcraft, we suggest checking out our Getting Started guide for more information on the game.

This is big news for all of our spanish speaking friends who would like to play WoW in spanish! So congrats to you guys, and have fun.