By Outland, I mean the planet/zone. I'm leveling my frost mage and priest and would like to know how bad the ganking issue is during endgame, considering I'm not too into PvP. How bad is it for both Alliance and Horde? See, I absolutely love TBC lore and quests and will be aiming to finish every zone; how hard will that be when it comes to ganking?
What Ferret said, really the difference depends if you're Alliance or Horde. You'll live more as Horde because there's tons on this server. Alliance is barely playable at peak hours, so expect to be ganked 5+ times every session.