In high school the least successful tend to be the more 'popular' ones in my experience.
And the popularity measure you speak of; the media; is not a measure of popuarity at all. In my opinion These people who are famous don't tend to be any more popular when it comes to close friends or likeability within their families. They are just as popular as the rest of us where it really matters.
I think most people grow out of wanting to be like the ones you speak of above. Often I feel bad for them. I would hate to have my picture in every magazine and newspaper just because I was spotted crying!
Amy Winehouse, Whitney Houston, Michael Jackson, Stephen Gately and many more have all proven that it's not what it's made out to be.
Popularity is measured on how well-liked a person is and I don't think these stars are anymore liked than we are when it comes down to the crunch. Well known, but no more 'liked'.