I'm seeing more and more jurisdictions requiring properly sized plumbing layout drawings (waste, water and gas) before issuing a permit, even on residential projects. I like the idea, especially since I can charge a fair price w/proper market up on it. Nothing like getting paid to do what I would normally do and then write off as overhead. My feeling is that eventually 3-D Cad will be the norm and not the rare exception. Time will tell.