I've looked around but I haven't seen yet where it is stated if there will be an open world area like SL, or if this will be individual user-created experiences only.
While the area we get for an expereince is pretty decent size, they really are not fit for vehicles/water/aircraft.
The experience I see as more like a fancy way to display your wares, a store. A social hangout, sure and some gaming exp. too, I see that. Not sure how thrilling it would be to just click a location and teleport everywhere, exp to exp. Part of the thrill is exploring the area. Scrolling through a list of exp isn't very thrilling.
No open world area? That could be a game-changer.