At GDC 2011, during a panel on the future of the strategy genre, GameSpot reports that Blizzard's Dustin Browder gave a little more info on when Heart of the Swarm might be coming out.
Browder stated that he expects Heart of the Swarm to be released in the "next six months to a year." That would suggest that the game could in fact be out by the end of 2011.
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