too early to expect 3d printing home use with personal designers.
can be practical in few years
That's why manufacturers can sell people's designs on
http://www.3dprintfilemarket.com . In other words, you can buy stuff off 3dPrintFileMarket.com by mail order. You don't have to have a 3d printer.
However, once you've experienced printing physical objects at home, you will never look back. This is because you can customize things. You don't have to own what millions of other plebians own. You can own somthing unique. For example, you can download a rose to give your SO for Valentines, but you want your rose to be unique, so you use
http://www.tinkercad.com to add the phrase Bibob Loves Amy on the rose. THEN, you print it out with your personal phrase "Bibob Loves Amy" on the rose. Or, you don't like the rose's shape, so you use Tinkercad to make the rose plumper and then print it out for your SO.
It's practical already. I've printed everything from vases, roses, handbags, to combs with it.
This entire outfit (handbag, dress, and shoes) was printed on a 3d printer:
Even mechanical devices could be printed fully assembled with no human labor needed to put together:
http://youtu.be/PPqLB-bv4gY