Hey there Popbilbo,
World Bosses won't need manual looting: you won't have to go over to the corpse and check what is there for you. Instead the Personal Loot system will directly place any loot that is created for you in your bags.
If that can't be done (for example, when your bags are full), then our friendly Postmaster will mail it over to you instead. :)
As Edgymyth mentioned though, loot is not guaranteed and your personal loot chance is not impacted by friends. If no loot is created for you, then you will receive gold instead.
Better luck with your future World Boss kills!