It did have sharding. If you did wPvP raiding in the last couple of months, you would know what I’m talking about. It is this:
This system is effectively sharding. It has been incredibly frustrating to deal with. You could be on the same layer as the enemy, yet not see each other. Or you could be in a full 40 man raid, then immediately upon entering the zone half your raid randomly disappears. These hidden sublayers made it impossible to do PvP events.
But it seems to have been changed or removed entirely, because the normal problems I have come to expect when doing large scale wPvP didn’t happen this time. Call it faction balanced layers (there were hidden sublayers) or whatever, I’m just glad they fixed it.