WoW - Wrath of the Lich King - Closed Alpha Testing

WoW Insider reports that the upcoming expansion for World of Warcraft, Wrath of the Lich King, has begun closed alpha testing:

We had some hints that this would happen soon and now WoW Insider has confirmed through anonymous sources that the next expansion, Wrath of the Lich King, is in closed alpha status, and that various players are being invited to check it out, under a strict NDA.