According to a recent Forrester Research survey, adult Internet users in the U.S. spend an average of US$81 per month on media products, and the way they pay for that content is undergoing a "fundamental transformation," wrote Forrester analyst James McQuivey.

"To thrive, media product strategists must shift to a model in which paid content is more virtual than physical -- and more rented than owned," McQuivey wrote in the report titled "People Pay For Content; They Just Don't Own It" published in March.

In a typical month, 18 percent of U.S. adult Internet users buy physical CDs, and 13 percent purchase songs and albums online, while 2 percent pay to subscribe to streaming music services like Rhapsody, according to the Forrester report.

Music subscription services got a bump up after Apple started letting these providers offer their services via applications from the App Store, said Gartner's McGuire.

These applications and other improvements have made Rhapsody and services like it more convenient and simpler for people to use, he said.