All systems can be exploited. You won't have to sit in a spot and grind the same 5 packs over and over. I can only imagine that npc behavior patterns will be predictable and you'll be able to manipulate them to some degree. So instead of grinding static mob spawns, you will be grinding local dynamic systems. I can foresee that 1 or 2 people may not be enough people to trigger major changes so a duo will be able to grind a local environment that is basically stuck in neutral.
There may be some kind of reputation system in place that prevents you from doing that maybe, like reputation or hatred, but that just end up giving players a way to kill even more mobs. To counteract that, they have to make it so eventually a mob of npcs spawns and runs you down like a truck and then hunts you down. Now that's cool. But will every player like that in their game? Will SOE tone down responses like that so players don't ragequit? hope not.