Apparently the public are unaware of RSS. I guess they must be completely clueless then about the Atom API that hopes to replace it. I'm not surprised by the survey result. I found that a friend of mine, not particularly IT-literate, had a blog. I told her that I was receiving her RSS feed. She apologised, and told me that it must be a virus on her machine. I reassured her that the RSS feed was a good thing. Knowledge of RSS is far from a prerequesite for being a blog author.
That said, every time I see Tim Bray talking about the latest blog statistics, the statistics are still going through the roof. So if the public don't know about RSS or Atom now, they soon will. They may never know them by name, but they'll get the idea - you can receive updates from blogs if you want, instead of having to check them manually. That's all most people need to know.