Today I've been playing around more with the new 3D world, making it a bit friendlier and snazzier. In particular I've added a human model to the world.
Of course like any physical item in the world it casts and receives shadows, but at the moment doesn't really do much, it's not animated, and it currently doesn't even rotate! But it's a start.
In the above screenshot you can see more clearly now the defined edges of the areas you can place objects.