Blizzard Entertainment officially announced the World of Warcraft: Cataclysm expansion.
Public beta testing phase for World of Warcraft: Cataclysm started, allowing players to test new content and changes.
The Cataclysm expansion for World of Warcraft was released worldwide, introducing major changes including revamped zones and new hero classes.
World of Warcraft: Cataclysm sold over 3.3 million copies in its first 24 hours, setting a record for the fastest-selling PC game at the time.