-Must of the Mark of Khorne. Mark of Khorne = +1 Attack [boo! hiss!] and Blood Frenzy (Blood Rage on a 1 or 2)
-Can have only Khornate daemons and vehicle upgrades
-The old sacred number rule is still intact (8 = daemon pack/beasts add +1 to a summoning roll)
Beserkers have "heavy close combat weapons.", AKA the same 4+ save rule that was exclusive to the World Eaters before. I believe they can have one plasma pistol for each 5 beserkers.
-The Juggernaught is only available as a gift of khorne.