Chris Metzen, Senior VP of Story and Franchise Development at Blizzard, went on the stage at the Sony presser and announced Diablo III is coming to the PlayStation 3 and PlayStation 4. It will have not only the single player campaign, but also 4-player coop mode.
Blizzard originally started out very strong in the console market, but in modern times hasn't been active. They have, however, constantly been hiring console developers, so it shouldn't come as too much of a surprise that they finally have something to reveal. But the fact that Diablo 3 is coming to the PlayStation 4 in the grand fashion that it was revealed today says a lot about their commitment to the game.
Metzen makes it known what their intention is: "Blizzard and Sony have entered into a strategic partnership, through which we will take over the world." Metzen went on to say that more information will be forthcoming, and to look specifically at PAX East.
The PlayStation 4 will be coming out during 2013's holiday season. For more information on the PlayStation 4 reveal, checkout Joystiq's liveblog.