Thar it is. Speaking of demons, I hope all seven greater evils are in this one! They've got to be, they've just got to be!
There are the three Prime evils:
Mephisto, the Lord of Hatred
Baal, the Lord of Destruction
Diablo, the Lord of Terror
Then the four lesser of the Great Evils:
Duriel, the Lord of Pain
Andariel, the Maiden of Anguish
Belial, the Lord of Lies
Azmodan, the Lord of Sin
Azmodan is already in D3 (link)
Diablo (obviously) is back as well
I haven't come across anything concerning Belial; hopefully all the others make a comeback--IF this is the last Diablo and there will not be any expansions.
I'm getting all excited going through this lore again... D3 come on!