PVP Zones

While raiding Ironforge tonight, we ran into the usual situation where the other faction chooses not to flag until we are in disarray from a guard zerg. Imagine instead that there was a way for us to temporarily turn the zone into a contested zone. Perhaps by killing certain key (and reasonably defended) npcs or taking certain points. I'm imagining it as a slow transition from a safe zone to a contested one, giving people who want to opt out of pvp time to evacuate or stop the transition. The contested zone status should also be on a cooldown to prevent a permanent state of seige in what is designed to be a safe place.