Diablo 3beta will be released in summer 2011. The announcement was made by Michael Morhaime, Blizzard's official, at a conference that focused on the group's financial results presentation Activision Blizzard.
According to Morhaime, beta will be released in July-September 2011. An official date for the final version has not been announced yet, the chances for a launch in 2011 winter season becoming increasingly smaller.
Diablo 3 was unveiled in June 2008, the game was in production for nearly three years.