Saw this earlier on another forum.
Most of the zones shown are very small and act more like tunnels than zones, seems to be the smallest world in any mmo at launch. Not comparing this world to other mmos with expansions btw, comparing mmo worls at launch. Even comparing this to vanilla FFXI it's very small.
Added to the inability to swim and the many invisible walls it does seem more of a confined shoebox than an open world. I guess once you get to 50 it doesn't really matter since you never need to leave town ever again to do any of the endgame content anyway. Seeing as all worthwhile endgame content is dungeons you just queue in dungeon finder and never ever have any reason to go anywhere else except around town.