While I see a use for the 3D printer in terms of accessories and possibly a model, the metallurgy involved in producing a working firearm is (at this point) well beyond a 3D printer. As you've mentioned, it may produce grip panels or other accessories but, as I understand it, these parts and components will not come close to withstanding the pressures required of a firearm. This may be the threshold of other capabilities, such as the production of molds for castings, but I doubt we'll see a firearm from a 3D printer in the foreseeable future.

Not that it has anything to do with guns but I saw a snippet about this kind of technology being used to reproduce human organs. Think its pretty interesting.

Designing and making your own fishing lures. Crank baits would be a piece of cake. Parts around the house for plastics that have cracked or broken. I see one of these in event home. Like a microwave.

Instead of a six-ounce cube of non-functional steel, the inventors could be using a steel barrel and receiver, but then the gun would not really be made by a 3-D printer.
This reminds me of the zip guns that kids used to make, using car radio antennas for barrels.

I would like to add that using one of these is nothing like using a standard home appliance. These are not simple machines. It takes a lot of skill and training to use one of these. Some people do this for a living. It's not like you can just pull up a picture on any old computer and make it in the printer. You have to be able to create a 3-d drawing in a special computer program and then download it onto the printer and that's just the beginning. Like I said I've done this before and I could hardly draw the model on the computer program.

There is no future in this. Although it was done it was done at a extreme cost considering you could go by a top end any handgun for far less than what it took to produce this one gun. As Ncarl said not everyone has the program to do this or the ability to do so even if they had the program which costs at minimum $4995. Then they have to have the printer which is not cheap and I think Jay's pricing is on the ultra low end (maybe missing a zero), considering a paper printer that I use here at work cost $15,000.

I'll be impressed when they develop a program to produce gold on a 3-D printer.

They did make one with one singular metal piece not printed out the firing pin. It did function. it however didn't survive many rounds before it fell apart. Its akin to the liberator pistol we dropped into France in WW2 they didn't survive many shots either and I think the whole deal of those was stamped for the most part. as far as one of those firearms being a threat to anyone like the media claims no... unless that's a last resort against a tyrannical government as a temporary means to allow allocation of their (tyrannical governments) arms. (i.e. the WW2 liberator pistol)