Blizzard on WoW Expansion’s Closed Beta news from 1UP.com:

Apparently, the goal of the closed beta, which hasn’t actually started, is to ensure a wide variety of players are represented. This includes PTR contest winners, BlizzCon attendees, raiding groups, guilds, and even some specific individuals. Netharea also stressed that players shouldn’t contact Blizzard about getting a spot; it won’t help.