Im really interested to see how it would print in zero gravity, hope they post some videos on the ISS youtube channel once they get it set up.
It seems like it wouldn't be really that hard, even given the whole "gravity" issue. From what the article said, it will use spools of plastic, which I assume means the printer is similar to a Makerbot. A Makerbot melts plastic from a spool and lays it down in rows, kind of weaving the molten plastic together so that it solidifies into one solid shape. The spigot just extrudes the plastic, and the platform also moves up and down with the model, so as long as the model is securely attached to the base, there shouldn't be any problems. That said, I really do want to see a video of it!
Haha, I can just imagine it being some top-secret method! The next video tour; "Yeah, here we have the kitchen, and behind this cabinet is CENSORED, which CENSORED our food for us." By the way, I didn't know they had 3D printers like that! The only ones I knew about that people could get were the kind I already described and another that just glues powder together.
Just asked my roommate about it(he works at the fablab) Its system is apparently called fused deposition modeling and the one we have isnt any brand a student made a cnc machine for his thesis project and it was hacked into a 3d printer because the school could not buy a one. Still cool but super low resolution.