If I want to print a mug I'd want it done in 5 minutes and cost $1, otherwise what's the point of owning one from the point of view that one of these will be in every household. Does anyone know if the current materials have any hard limits on them as to how fast they can be manipulated for example?
This capability is useless if you're making mugs but it is priceless when you're prototyping.
Making mugs is entirely the wrong application.
Any specialized machine can absolutely annihilate the volume printer on the basis of cost, and for many things also on the basis of quality, but you have to produce thousands of units to pay for the machine.
You don't even need it to be a prototype. You just need to be making something that no one else needs--or not enough other people to warrant building a specialized machine to make that thing.
But then, if you do need that specialized machine, maybe there only needs to be one of those, and you have just the right sort of machine to make unique items....
Nothing beats a cheap ceramic mug for mug-ness.
And that goes for pretty much any one-off produced with a 3D printer that attempts to re-create a mass produced item. It'll be more expensive, more fragile, less pretty and in general less functional and strong.
For mugs, that means constructing a plaster mold, then using liquid clay (slip) to fill the mold. The clay is dried, glazed, and fired. If your mug design is not already unique, someone else already does this faster and more cheaply than you can. But if you want 20 mugs shaped like your own head, you're still only going to volume-print one copy.
Or maybe you're making mugs out of food-grade silicone elastomer instead of ceramic. You still only need one printed copy.
The point is not to make a mug, the mug is a benchmark. The point is that it takes a nontrivial amount of time, the model readily available, it is repeatable, and it has some very interesting properties WRT complex curves and overhanging structures.
(Like all benchmarks, we can argue from now to forever whether it is a good benchmark.)
Granted, there are many online services now which will 3d print parts for you with very high quality and about 1 week turn around, so owning your own 3d printer is not always a good financial move for a business, depending on the desired uses.
For the person printing things on the average "cheap" printer, they're not typically concerned with the longevity aspect. Most 3D-printed things seem to be the opposite for mainstream applications. People keep using examples of printing "stuff you can't get at Walmart" and implying the printed parts are expected to be used for many years in an environment that will have some moderate amount of wear and tear.
3D printing not only needs to get faster by an order of magnitude, the quality of the output component needs to increase substantially as well. You need to be able to print in colors and wind up with a finished product that looks close to the quality of an injected molded piece.
In our current throwaway-oriented manufacturing and product distribution civilization, it irks me to landfill perfectly good objects for want of a very small plastic part. It isn't the gross materials cost compared to the mass-manufactured cost that I evaluate in these situations, it is the logistical tail externalities cost I impose upon my descendents for landfilling objects that could be used with a modest (to my income level) investment in repairing it. This observes the "Reduce, Reuse, Recycle" mantra by reducing the waste stream through repairing.
There is a rant embedded there, on waste streams are a sign of technological backwardness as a riff on Iain Banks' "money is a sign of poverty", but that's for another time.
A couple of examples to illustrate.
A door bell ringer that has a base mounted to the door frame and then the housing slips over the base and latches in with a simple catch in the base. The housing was ripped off the base (toddler Destruct-O-Tron), and upon inspection it was the simple catch that tore off. The catch is the size of a fingernail clipping. It's long gone.
Customer service at the manufacturer was sympathetic, but unable to help; they acknowledged they had the bases, but it just wasn't in their procedures to send it separately even if I was willing to pay for it. If I have a 3D scanner+printer, I could create another base with that catch, instead of ordering an entire ringer and landfilling a working ringer for want of a fingernail-clipping size piece of plastic. When I ordered the replacement ringer, I not only threw away the plastic, but also the PC board (though I salvaged the battery), and contributed my small part to converting nasty bunker fuel oil into emissions and engaging the exhaustively long supply chain it took to create the replacement ringer (including a few drops more oil to create the virgin plastics that went into the new ringer).
That's just me, but multiply by billions of people making similar decisions over the next few decades as a burgeoning global middle class arises from the externalities wreckage wrought by our current globalization implementation, and it gets ugly fast.
Another example. A sippy cup is designed with a small plastic rocker at the top that lets a straw flip up and down [1]. That rocker can be pried off, and eventually is lost somewhere in the house until a few years later when it is found in some nook. Without the rocker, the cup leaks when upside down. The manufacturer has stopped making the product, in favor of a new version with an incompatible rocker; this manufacturer turned out to be willing to ship just replacement rockers, but they only had the new style on hand. Off to the landfill the cup goes, and I order replacement old style cups from dwindling retailer inventories. Unless I have access to a 3D scanner+printer.
The state of technology is sufficient as-is today to let me more than satisfactorily solve these situations without resorting to a replacement purchase, and about 1-3 instances come up every week. Double that occurrence frequency if I got a metal laser sintering 3D printer. I could refine various products with small, custom silicone bumpers/insulators/grips/etc. by creating silicone molds with a 3D printer. The applications only increase as the 3D printing technology advances. These are only the simple, obvious applications; much greater changes and improvements in industrial product design, manufacturing, externalities reduction, sales, marketing, support and distribution lie ahead when we combine these immediate applications to other developments.
[1] http://c3.q-assets.com/images/products/p/mc/mc-083_1z.jpg