Now that Blizzard has Activision, undisputed masters of *ahem* "getting the most out of a franchise", looking over their shoulders, would a console port of Diablo III really surprise you, were it to happen? OK, no, look. Calm down. I said were it to happen. Because while it's not confirmed, or even strongly hinted at, it may happen. May. Because Blizzard's Rob Pardo has said that it's a "theoretical possibility", and that "of our major franchises, [it's]the one that's most console friendly, for sure". Pretty sure he's talking about the 360 and PS3, there. Can't see Mii support and friend codes really fitting with the whole gates to hell thing.
Console Diablo "theoretically possible" [Eurogamer]