Speculation: It seems like the earliest type of PVP in this game might come in the form of FFXI's Conquest mode, where we represent nations as we're killing enemies in a given territory... but perhaps representing a Grand Company on quests/levequests/killing enemies.

As dull as I might sound, no direct PvP unless it's on a horde of rank 13 lalafell conjurers that suspicously teleport to Horizon en mass and do nothing, then teleport away.