Back in the old days, you had to take care not to aggro too many mobs, sometimes you even had to fight your way through a number of mobs before you could get to the one you wanted!
The good thing about World PvP, is that it's a numbers game, everyone can participate even PvErs who may not know how to PvP well, it encourages people to bring friends along, maybe you'd even make new friends.
Flying mounts however, you will never engage with the terrain, you will rarely engage in WPvP, you will never group with other players to overcome something. There is no mmorpg interaction other than that between the player and their quest tracker on their map.
I just have my fingers crossed it will be a no-fly zone.