This article at /. covers a press release given out by the RIAA, and covered at Salon Magazine which says that CD sales dropped by 39% last year, and they're blaming it on Napster. If you look further down the article, they're actually only CD SINGLES that dropped in sales, and not albums, which actually went up in volume. CD Singles are about 1% of the industry's total sales, so, basically, the music industry lost 0.5% of their total sales of $14B+, which may or may not be due to Napster.
Read it for yourself.

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