I'm sure there are people who have no idea, although I can say that I've never heard it used in any mainstream news or entertainment-related programs. "Cougar" seems to be the media-safe replacement that I hear much more often on those kinds of shows.
Awhile back I was in the car with my mom, and it was on the bumper sticker for a vehicle in front of us. My mom has the annoying tendency to read aloud bumper stickers that she sees, and I was bracing myself and cringing at the thought of her repeating it and then asking me if I knew what it stood for. Thankfully, she didn't even seem to notice it.