This could turn into quite the argument. How environmentally friendly, or 'Green' is 3D Printing?

On one hand it is cutting down on the waste of subtractive manufacturing, while also leading to less fuel use in shipping products to market, but on the other hand 3D printing can also create more plastic in the environment, hence more pollutants. The following article looks at both sides of the argument: http://3dprint.com/6388/green-3d-printing/

What do you guys think? Is 3D printing a net positive or negative for the environment around us?