Personally, I don't see how people could not know this is going to happen. It's been all over the news for the last several years and for the better part of the last year tickers and commercials have been on TV explaining the switch over.
Partly, I'm astonished anyone but a very small percentage still recieves OTA signals, but I digress.
Personally, I think those of use awatiing, wanting and loving the digital revolution should just leave the luddites behind.
Well, more people would know about it if they slipped it in the daily reports about Angelina Jolie's 20 kids, Britney's latest crisis, etc.
I've been aware of it forever, but the average Joe Sixpack barely knows how to turn on his television. Being aware of any tech-related stuff is not going to be on his priority list.
I know it might be a bit cruel, but I think the broadcast world should all collaborate on a practical joke and start running a broadcast about the strange objects descending from the sky around the world and wondering about hostile intentions. Then they should say that they'll stay on the air as long as they can to get reports on what the situation is with these objects and possible aliens. Then the analog switch gets flipped to digital and suddenly they get nothing.
Hilarity ensues.