Neither Hot nor Cold on This One
I've looked closely at 3D printing closely and, while it's a great tool, it's only a tool. First, many materials (e.g. many plastics) can't be printed at all, or easily. This cuts down the choices considerably. Second, 3D printing is quite slow compared to, say, injection molding or stamping. It's a great prototyping tool, and it will create the ability to do limited runs or 'one off's' that can't be done economically otherwise. You can also potentially reduce parts counts and shape parts that can't be made in other ways. These are exciting new applications that will create new businesses and products. But, I can't see mass disruption of most goods - ever. Also, if it's so good and inexpensive, every country will have these tools so the playing field will still be wide-open.
