The way I remember it, at least on my server, is as the zerg grew larger so did its balls and advanced slowly for us the horde at least. LOL There was actual fighting but it resembled a zerg ball vs another zerg ball with leeroys running in from time to time, lol, and of course mages and ranged taking pot shots. This actually got worse since they added in the honor system in before they added the actual battlegrounds, lol.
World PvP almost always consisted of you questing and then a rogue which was 10 lvs higher would gank your ass and then proceed to farm your corpse for a while until he got bored or you rage quit the game.