Well, I don't see anyone really heading down the Google route (including Google) until someone figures out how to really capitalize on the sale of the printable models... And that would mean pushing for DRM on proprietary files, which is both bad for everyone in the short term and unprofitable in the long term. And there's no way to make printing of any kind into an advertising vehicle without being universally hated. (Looking at you fax-machine-spam-mailers, IMO the primary reason the entire medium went extinct at the first possible opportunity)

Besides, Google is kind of a special case, since their advertising is just the company's fuel, not the sole reason for them expanding fiber internet everywhere. Their goal (which they don't even try to keep secret) is nothing short of an AI-controlled utopia that scares the hell out of a lot of people.

Now note, while I said that the existence of a sub-$500 printer price point would get other companies to populate it, doesn't mean many (or any) of them will be printers anyone will be proud to use for making display pieces... Even if Makerbot and 3D Systems whip together $400 printers, I wouldn't want to buy them unless the savings were from a really new method of construction, the way the MOD-t is. Though there are some exciting things still happening with RepRap (I'm betting PrintPi alone might knock around $100 off the average cost to build a RepRap if it becomes commonplace and I am a gigantic fanboy for the GUS Simpson and am excited for GUS v2), the traditional setup consisting of stepper motors with rails and screws on the z-axis can only go down in price so far before quality suffers tremendously.