I concur with aaronb
it needs to be one or two things:
1) easy access
2) good loot
or both
Only outdoor PVP zone anybody goes to is 2h0 and its way too cramped
I want a battlefield.
Maybe just a special outdoor shop term between the two entrance points that sells good loot you cant get anywhere else.
That alone is enough incentive to control I think.
-BW