Oh, I don't see it as a serious new content creation tool. It's just a nice feature to have. Say a good sculptor was just messing around in dreams and modeled something that actually looks pretty good. He has this neat option to export it so he can re-model it in maya or what not if he so wishes.
Or, imagine your daugher made this beautyfull piece in dreams, and you can export it and 3D print it somewhere. Now that is very cool.
I don't think it will be super widely used, but definetly will come in handy for a few people here and there.
I was surprised by MM giving option to use Dreams model in Unity or other polygon based rendering Videogame engine. I think 3d print option is more useful...