If you google their site you'll be able to find the features. But this idea/concept is pretty damn new. Most 3d printers are confined to a small working space and apply material in layers whereas this uses a 6axis industrial robotic arm to be able to print without support structures. The guys who made this are currently printing an entire metal bridge on location.
Hmm. I see the website but I'm not seeing anything about a bridge. You have a link to the project? I have to admit, I'm a bit incredulous about this upscaling to an entire bridge, especially one that's meant to be both load bearing and permanent.
I just started working with a Makerbot Gen5 Replicator a few weeks ago, which prints with plastic. One of the primary limitations is that the extruder heats up the plastic to print which makes the material soft when it first comes out. This means that undercut objects and cantilevered pieces are more difficult to make right because the material will slump as it leaves the nozzle. What's nice about welding metal like in the video is that the material is instantly strong as soon as it gets made. Much more flexibility that way in terms of what can be created in a single 'print'.