What is the potential for 3-D printing?

I think 3-D printing will happen, and indeed already is happening, but I don’t see that it will bring a utopian new future.  From a recent New Scientist article (gated, related version here), here are two points:

…it’s difficult to print an object in more than one or two materials…

And:

…these combined hardware and materials issues mean that only a relatively small proportion of all people will end up printing out objects themselves.  A more likely scenario is the growth of online services like Shapeways…or perhaps neighborhood print shops.

Maybe I’m blind, but I don’t yet see this as a technological game-changer.  It seems more like a way of saving on transportation costs.  To put it another way, what’s the huge gain of making everyone a manufacturing locavore?  Perhaps there will be some new flurry of home-based innovation, based on tinkering from what these printers can drum up, but that seems to me quite speculative.