Blizzard will probably just release it without telling anyone... on April fools day or something mean like that.
Either that or at the end of the five part comic they have going.
Heck, it's anyone's guess but it'd better be soon. =/
I have heard that Blizzard released that they are going to release a date soon that would tell us when they want to release the game. I believe the exact thing they said was "In the near future", so we can only hope. We all know Blizzard is famous for pushing back games, but I'm assuming they do this to perfect their godly game :D. So the only thing we can do is wait and hope that Blizzard is almost done crafting their masterpiece!
I have high hopes for D3 and I can't wait for it to come. I am going to say it will arrive in Mid-May. It just seems like that is the amount of time Blizzard will need to polish everything. I always hate how long it takes for them to put out a game, but really they do it better than anyone else. They take their time and listen to their fans and get things right. I am so ready to sit down and come back to sanctuary. It has been too long. Can't wait to see you all on there.
"Once more into the fray, into the last good fight I'll ever know, live and die on this day, live and die on this day."
I would expect they anouncer it at a bunch of places at once. They hit us with the twitter, facebook, and real life event combo that send all fan sites and fans in a mass hysteria. Accomplishing more than what they had expected to accomplish.