"I'm sure 3-D scanning will have a place, but it is hardly a panacea; nowhere in the foreseeable future are you going to be able to point your "Instamatic Scanner" at a prototype and send the file out to Shapeways to get a model back, and certainly not anywhere near a price modelers will feel is reasonable."
We are a lot closer than you think. MakerBot already has a scanner available that will scan an item, and make a file that can be sent directly to their printer. It does not do the quality you and I would want, but I am 58, and I think I could see the day when it will do what we want. Ten years ago I would have said, "what is a 3d printer?". Now I own one!