I'm curious what measures have been taken to stop PVP'ers from camping the shrines just to gank the arriving players.

Not that I would stoop to such horrible tactics again.. The rogue in me is just curious.

Given that you can only 'gank' in consensual pvp areas, that seems to be a valid tactic to me.

We can only speculate, anything else would fall under NDA (if someone was already able to see it during AvA beta event).

High level NPC guards positioned around shrines would be a possibility (if a shrine can only be held by one faction)