If you're on a PvP server, world PvP is what you signed up for IMO, give it and take it. The Charred Vale questing area was a nightmare for me at level 19-23ish. I was repeatedly ganked and corpse camped by groups of lvl 24-39 horde with a 10 minute corpse run to follow. Even the alliance I grouped with at the time kept saying "don't attack them", they told me they had some sort of 'scanner' and knew where the horde were, I now have very strong suspicions that they were Blizzard employees, the same players don't even hurt a fly now.
Now that I'm level 60 I have absolutely no qualms whatsoever about killing any Horde under any circumstances. Nothing gives me more of a kick than to run up to a level 42 player who's just had a long fight with a mob and to give a quick mind blast to finish him off before he can loot. One of my other favourite pastimes on WoW is to gank Horde who are happily grinding in Tyr's Hand for their repair bills :D. When the alliance tell me not to attack that only gives me more pleasure. In fact I'm flying to Tyr's now from Ironforge whilst writing this. Happy PvPing.
