The Long Tail: FAQ: Does the rise of the LT = the fall of mass culture?: "Likewise for music. By my count only ten of the top 100 best-selling albums were released in the last decade, and only four of those were in the last five years. Occam's razor says this is more likely due to the diminishing power of radio as a hit-making machine than it is to some Darwinian decline in music talent. "
Ummm - or maybe the fact that a lot of them have had an additional twenty years to rack up their sales figures?