A reward/risk system should be put in as well. The masses will not PvP if there is no reward and without risk it almost makes it pointless. Make World PvP deaths damage gear or endurance until repaired. Also a leader board so people can see who the biggest PvP'ers are, World PvP ranks/titles. these little things can encourage people to join the action.
I've gotta disagree here. The masses will most definitely PvP if you start fighting them. Get a group of four people together, cause some chaos, stir the hornet nest. Everyone is on edge in the PvP zone, it doesn't take much to get people firing on each other. And causing damage to gear only further disincentives PvP, because who wants to fight if it is going to drain their unrelated funds? Old Ilum had rewards for open world PvP and it was abused to the point of insanity.
You shouldn't need a reason to fight other than a desire to fight. The point of the event is to get a bunch of people together so that they can fight, the objective should be secondary if you want to fight people. I've had the most fun since the days of old Ilum when we actually got groups together and fought each other in random encounters. Except this time there is no faction imbalance to be concerned about.