Implement PVP and be aware that stat balancing might become an issue, just like in WoW. 1 spell oneshots players in PVP, and is balanced in raids. So they nerf the spell to make it no longer overpowered in PVP, then PVE'ers complain and the QQing never ends. I solely play for PVE in RPG games. If im after pvp action, I play Halo Reach, BlackOps etc.

If SE does implement, they need to create spells and abilities just for pvp use. Otherwise, both pve and pvpers will end up hurting. Just my views on the issue. I might be wrong, but i got so annoyed about constant changes in WoW, that I quit and now enjoy lvling my Con/Thm.