I have several prototypes made with 3 d printers using starch on an ink jet style printer or acrylic plastics on an SLA system (sterio lithography) but an inkjet printing low resistance tracks is interesting.

I can see mounting components on these using chemical solder to prevent heat damage to ajacent layers.

Actualy I believe that the possibility of this was in a recent previous topic. I can see some interesting physics problems if they are printing both the traces and the filler as in sla or z corp.
Other alternatives would pose the via and plate through issue.

Anyway they will make it work commercially and in 5 years these could be as common as colour lazerjet printers.
Dam I was born 25 years too late to be a real part of this type of exciting technology.
Terry