Blizzard Entertainment announced today that StarCraft II: Heart of the Swarm sold through 1.1 million copies worldwide during its first 48 hours. This includes physical and digital copies, though a breakdown of sales between the two was not divulged.
Heart of the Swarm is the first of two expansions for Wings of Liberty. The third and final entry--Legacy of the Void--is currently in development and has no release date. It will focus on the Protoss race.
For more on Heart of the Swarm, check out GameSpot's review.