The article suggests the postal service 3D printing from their own facility. Is there is precedent of the post office even printing ink on paper and shipping it on behalf of others?
The only one I can think of was when people could write letters to soldiers in WWII by having them scanned onto microfilm, flown to a closer post office, then printed and delivered. http://en.wikipedia.org/wiki/V-mail
They are desperate and with good reason - they've been screwed by Congress.
They are just suggesting that 3D printing businesses locate themselves close to postal facilities so that they can quickly ship things. 3D printing hubs is a bit of a misleading heading.