Since there is no more penalties for killing civilians, will there be more PVP on PVE servers?. I beleive so.
Yesterday two hordies roamed in Westfall killing everything (civilians and those marked for pvp) they came across. They were level 54 warlock and priest, and thus at a much higher level than those normally playing in that region. We managed to kill them after a while after we assembled enough people. I must admit I think its quite amusing:)
I suppose several guilds will do raids into enemy territory just for the fun of it.