3D printing will revolutionize manufacturing. Not home manufacturing.
Many people think how great it would be if they could print anything they needed at home. And yet plain paper printers are great example of how printing it yourself is not for everyone. A printer no matter how small still takes up space. The feed is not free. The power to run it is not free. The cost of the items in local stores would be extremely low partly due to competition from people who do own their 3D printer.
3D printing could result in smaller factories closer to large urban centers. It will not destroy the shopping district in large cities. But the shop in small town Main street could be screwed. But again, that's mostly to the larger trend of urbanization, and the ever shrinking populations and visitors in small towns.
NOW it's your turn...