not new. http://en.wikipedia.org/wiki/Direct_metal_laser_sintering

It would be interesting to see the results of various load tests.

DB - It not be totally new, but if they get this idea working well, all sorts of costly casting and part assembling processes will not be needed, hopefully dropping the costs of many items. Too many machine parts are made from tiny components as there is no way to "work around corners" or "put tools into closed spaces" so costs rise along with the difficulty.

I am curious about the strength of such structural elements. Being no expert I wonder if these could be used for critical load bearing parts? Can they match (or even surpass?) the structural properties of classic metal parts used in construction? Other than that, I think the technology has a bright future in construction which is by large extent based on custom work (at least compared to autoindustry etc.).

@ Short Fuse I've seen DMLS parts properties being listed as % of the same properties from parts made by casting, that are usually lower than those of machined parts that are usually lower than those of parts forged to shape... With DMLS you end up with a structure that might have a certain degree of porosity, you might increase the density through Hot Isostatic Pressing (HIP) but still it won't match the structural properties of traditionally manufactured metal parts. On the other hand what you get is a much greater freedom of design, as shown by the example pictured.

What worries me is that today there is a restricted set of components that can be bolted/welded together to form structural members. Thus, when the known structural strength of the steel used in them is added to the equation, it is possible to define quite precisely what their failure pattern will be and thus whether they are strong enough.
A completely different situation exists with these members. Imagine the hoops a designer had to go through in order to sign off the above design as being of sufficient strength to resist the loads it was going to meet in service.
I don't know, but I imagine that being sintered, crack propagation will be a major consideration of the designers wishing to specify such components. Sometimes progress takes one a step too far.

@ Mel Tisdale & Giolli Joker - Classic laser sintering will create a porous metal as you say, but there are new processes that do not. Electron beam fusing melts the layer entirely as well as a tiny part of the previous layer so the final part is actually one solid peice of metal. Laser sintering has also been advanced to fusion by allowing the beam to linger slightly longer on target accomplishing the same affect.
If traditional sintering were used the new SpaceX Super Draco thrusters would break very quickly due to cryo cooled liquids infiltrating the metal. The new fusing methods are what enable their 3d printed motors to function.

By printing the component you can get shapes that can not be put together in other way and having a single piece instead of several pieces held together by fasteners you could end up with lighter structures per strength even if the metal is not as strong.

I am dead certain that we can make gains with this technology as far as the artistic as well as the strength and safety of numerous products. But as we create new shapes that do not have a clearly identifiable history there will be commercial issues on how to order parts made with 3d printing. Your new, wonderful L bracket may look nothing like a traditional L bracket. So how do you order three hundred more of the same? I have seen pics on wonderful, structural beams that would defy any machine shop due to their intricate and complex variety of shapes. Walls can be a continuous sculpture as can ceilings. And that is without adding complexity or cost to a structure. No technology comes close to 3d printing.

Regarding the strength of 3D printed metal components, General Electric and Snecma have a common facility in Toulouse where they are making the turbofan blades for their jet engines in one piece instead of about 200 pieces, they claim, stronger, faster, lighter and cheaper.
Also BAE and Lockheed Martin are using 3D printing:
https://www.youtube.com/watch?v=perMGY0oajs