It seems pretty obvious the way this is going to turn out.

In the next 1-2 yrs, we will begin seeing 3D Printing come to retail stores like Walmart, etc. A few nerds and people that like gadgets will get printers in their homes. However, most of the "in-home" printers today are not really all that great when it comes to printing everyday items. In store printers will be able to print in just about any material possible, while most at home printers are limited to plastic.

I think in the next 3-5 years we will begin seeing affordable printers that print in multiple filament types. When this happens, more and more people will begin purchasing printers for their own homes.

So my guess is retail first, and then in homes (at least on a broad scale).