I'd agree, Michael....quite a difficult issue.
There is such a defining line about what people consider art, and what they consider popular, and then even trash. I think YM brought up a superb thought when he mentioned Norman Rockwell. He was basically considered an illustrator...but his work has been proven to many to be art...I happen to have 2 pictures in my office by him (obviously not originals!!!) but when I look at them they say so much...they tell a story in one solitary picture...there is so much going on..and so much you can read into them....and maybe that is what art is all about.
Michael, Do you ever discuss topics such as these with your students...I suppose you do. I wish I could have had you as an instructor when I was in school.....

I think you're right about Rockwell. As a child, I used to admire his coverwork at my great grandmother's--she was a fan and subscribed to mags that featured his work. Same is true of political cartoonists--there's quite a few of them I'd like to have framed!