Guessing I'll be that guy who goes against the feel of the thread, but 3d printing is pretty awesome for some stuff.
Not trying to toot my own horn, but when I did the Supernatural Horsemen rings, the ability to have those in metal for what would be a LOT cheaper than involving a jeweler, 3d printing kicks ass.
Same goes with the skyrim skeleton key I did, and the Namira ring. If I didn't have access to a kick ass modeler, and a place like shapeways or ponoko, that would not happen.
The Jor El crystal mask from the first Superman movie is only going to happen because of the 3d modeling "craze".
Now, with that being said, not EVERYTHING needs to be 3d printed. I can understand some stuff, I forget the guys name, but he had articulated iron man armor made, which is just... astounding, needs to be 3d printed like the examples i gave. Some stuff though, really doesn't. You can clean up the masters and offer castings.
All 3d printing does is give more access to more stuff in more ways. It's a tool, just like clay is. I'd imagine the stone cutters back in the day were complaining about people mixing up clay and sculpting things instead of hammering em out of rock like they always had done before.
I don't agree with the idea that EVERYTHING needs to be 3d printed, but having the ability TO 3d print is pretty awesome for when you want to make something that normally would be cost prohibitive.
Chris