"There's still a cultural divide between Apple consumers and the rest of the computing world, and that's especially apparent when it comes to the way they interact with music," said to Russ Crupnick, vice president and entertainment industry analyst for The NPD Group. "Mac users are not only more active in digital music, they are also more likely to buy CDs, which helps debunk the myth that digital music consumers stop buying music in CD format."

NPD's consumer panel data reveals that unit-volume sales share for Apple computers increased from nearly 6 percent in 2006 to almost 9 percent this year. Overall, more than 32 percent of Mac users reported purchasing CDs in the third quarter of 2007 vs. 28 percent of PC users, and Mac users were more likely to listen to music as well as watch videos on their MP3 players and computers. Some 34 percent of Mac users had uploaded music to their MP3 players, according to the study, compared to 16 percent of PC users. Further, 56 percent of Mac users reported listening to music on their computers vs. 31 percent of PC users.

"While the market for digital music is growing, it's growing slower than many would like it to -- CD sales are still declining and digital music has not replaced those lost sales," Crupnick said. "The more consumers become comfortable paying for digital music, the more chance they will evangelize to others. And at this point in the game, it's the growing base of Apple consumers that are the industry's low-hanging fruit when it comes to converting from physical to digital music."