Rob Pardo's keynote speech from Sep 2006

[Monkey]

Outland rocks, Artega. If you're a quest monkey, there's quests galore. There's PvP stuff in every zone, and of course, other than Shattrath, it's all contested, if you're on a PvP server:P There's stuff to grind, if that's your way, and there's 5-man instances out the wazoo. There's even convenient travel once you get to Shattrath.

Shattrath is also actually the "safest" city on a PvP server--even in Stormwind or Orgrimmar, it's possible (if you're flagged) to be killed by the opposite faction. But there's no PvP in Shattrath. Everyone is flagged, but you can't even accidentally attack anyone.