Juggs in rage are just AoE gimmicks, and Mara rage will be equal to it in 1.2. They can pull good dps, but Mara's will kill stuff faster.
Utility Wise
Jugg has Charge, Intercede (charge to friendly target), and AoE slow, a knockback, taunts and guard.
Marauder (Annihilation)
Charge, a Slow, -20% healing debuff, Predation (movement speed increase and damage reduction for whole Ops (in 1.2)), Berserk makes your Bleeds heal your party, Force Camo (invis for 4 secs), Undying Rage (99% dmg redutcion for 4 secs), Obfuscate, etc.
Utility Wise
Huttball Jugg >/= Marauder
Others and PvE (DPS Spec Only) Marauder >>> Juggernaut