Two things that struck me (excellent find, by the way) were that there are still an awful lot of humans involved in the build process and everyone seems very relaxed, almost casual. There's no rushing about or anything.
Well, yes, but this is a promo vid is it not? They are hardly going to show it when everything goes to s*** and they're haring up and down yelling "turn it off turn it off!" while the robots weld 6 cars together and then make a break for it through the nearest wall.
I've worked on a high tech fab line before and whenever there are visitors, let alone videos being made, they are very careful that there are lots of people looking very busy yet completely calm and relaxed. They might even mute the alarms, just in case.