Starting today you can go and sign up for the World of Warcraft annual pass. By making a 12-month commitment to World of Warcraft you will get Diablo III free when it launches.
In addition you will also get guarantee access to the next World of Warcraft expansion beta when it goes live. You will also get the Tyrael's Charger mount for free.
That new annual pass, which you can pay for monthly, is live on the site now.