I'm 21, and it must be said that by any standard I'm extraordinarily ignorant when it comes to music. (e.g. I'd never heard of Meatloaf until about 4 months ago, which my friends kept telling me was really shocking, so I had to go and look him up. Ditto for J-lo in my first year. Oops.)
I had heard of Amy Winehouse, but it must be said that this is the first time I have ever heard anything positive said about her. The only tone in which I'd ever heard of her previously was incredibly derogatory. Now that I've read through the thread and her big cultural presence has been explained, I'm actually a little more saddened that the only perception I've ever had of her was so dismissive and negative.
As for her music, I've never knowingly heard it. If it's as popular as people say it is, then I've almost certainly listened to it without realising. Would be interesting to listen to her albums and see what I have/haven't heard.