yes its a multiplayer RPG!
but you dont not BUILD with other people. the game is misleading as a lego game.
the puzzles with building make you do it alone in instances.
and freebuilding once again puts you ALONE in an instance with a lego-creator like system.
so NO, you build ALONE on lego universe MMORPG
and show off your build later as just a model.
thats not building together at all