You did not expect them to fully open all worlds as soon as maitenance was over, right...? They now need to fill in the new spaces for each server, old and new (do remember that Worlds not support ~7500 players). And it seems server capacity may be increased FURTHER if needed, maybe to 10000 players.

To this, add optimizations to increase the amount of players ON SCREEN (mainly for PS3), which I hope are soon to come.

Do not expect servers to be fully opened anytime soon. Battles take days; wars take years, and this is a war to achieve the game's success.