Yes, it's likely been set up as a media event, probably days if not weeks in advance. That news video aired last night on local TV during the 9pm newscast, so apparently production started Monday instead of today (it actually takes a day or more for a given vehicle to go down the line start to finish). And if you look real close, at one point you can see the cab of a white truck between a couple of vans in the background to the right. That implies more are on the line.
It's common for automakers to run a handful of a new model off the line, then halt for a couple hours to do a media event. It helps boost recognition in the plant's region, in this case Wentzville MO and surrounding communities, as well as validate the efforts of workers who helped get the new vehicles out. I think it's great. Now if only GM would update that 30 year old van.....