I did hear the slick message in the background of the KTLA link above. Turns out my link was not the live over-the-air signal, but a internet only link. When I was able to finally get up the over-the-air video, they were not playing that video at all.

Kind of disappointed in that. I thought it would have been more impactful if it was simulcasted on all the channels at the same time. To effectively have an entire metropolitan area come to a stand still for 2 minutes, I think would subconsciously show how serious the content of the drill is.