Blizzard Entertainment announced this week that World of Warcraft's subscriber base has exceeded 11.5 million units following the November launch of the expansion pack Wrath of the Lich King.

Wrath of the Lich King sold 2.8 million copies in its first 24 hours, and 4 million in its first month, beating both previous records held by Blizzard's other WoW expansion, 2007's The Burning Crusade.

WoW had just hit 11 million subscribers at the end of October.

In mid-October, analyst Colin Sebastian said he expected 1 million new WoW subscribers would join during the course of 12 months.

GameStop SVP of merchandising Bob McKenzie said in a statement, "Not only is Wrath of the Lich King still doing well, the base World of Warcraft game and the World of Warcraft Battle Chest are performing better than last year.
"That type of traction is very impressive for a game that is going into its fifth holiday season and speaks to the enthusiastic player base Blizzard Entertainment products have."

Blizzard said that it is currently hiring to keep up with development activity.

The company defined "subscribers" as: "...Individuals who have paid a subscription fee or have an active prepaid card to play World of Warcraft, as well as those who have purchased the game and are within their free month of access. Internet Game Room players who have accessed the game over the last 30 days are also counted as subscribers. The above definition excludes all players under free promotional subscriptions, expired or cancelled subscriptions, and expired prepaid cards. Subscribers in licensees' territories are defined along the same rules."