Announced on the Diablo III blog today by Mike Morhaime, the release has been pushed back to make sure it has all of the polish it needs:
While this news might not be a complete surprise, I know that many of you were hopeful that Diablo III would ship this year. We were too. However, this week we pulled together people from all of the teams involved with the game to decide whether we felt it would be ready before the end of December, and we grudgingly came to the conclusion that it would not. Ultimately, we feel that to deliver an awesome Diablo sequel that lives up to our expectations and yours as well, we should take a little more time and add further polish to a few different elements of the game.
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