Unlike the old wilderness when you kill some one you do not get their stuff. You may get one of theres items and then some other random stuff. Say the person you killed lost a dragon scimitar,you may get a dragon scimitar,a bandos statue and some other random low value items. Your loot is also based on ep ( earned potential) you get 25% ep for every half hour you spend in a pvp hot zone. Also in a pvp world you can go any where in the world of runescape you wish and still be able to attack people.
Hope that helps and if you have any other questions feel free to private message me