I was 16 when Elvis died. I was 19 when John Lennon was murdered. Seems to me John Lennon's death brought in more coverage than Elvis's death.... then again, at 16 other things preoccupied my mind.
Michael Jackson was in a class all by himself. Michael Jackson's music, at only 50 years of age, spanned several generations. The only time I was ever a fan of his music was when I was a kid (I'm 2 years younger than he was) and he was singing "A-B-C," "Ben," "My Name Is Michael.." Still, I was aware of him and the influence his music was having on the world.
So, I think his death will be in a class by itself. He started making an impact on the music world in the late 60's, early 70's.