A new report from Jupiter Research forecasts digital music will contribute 41 percent to total recording revenue in the U.S. by 2013, from the 18 percent it represents today. This is based on a compound annual growth rate of 17 percent over the next five years.

However, this figure will not compensate for falling CD sales. The company sees an overall drop in music industry revenues from today's $10.2 billion to $9.8 billion-a negative compound annual growth rate of .8 percent by 2013.

In five years, over half - 55 percent - of Americans will be purchasing downloadable music, but only 24 percent say DRM-free sales will influence their decision. Another 75 percent of the population will own MP3-capable phones by 2013, but most will use them to play sideloaded music. Jupiter says over-the-air download sales to mobile phones will contribute only $300 million to the pie in five years.

Subscription service will be no help either, with the company projecting slight growth from 2.7 million to 4 million music subscribers in the same timeframe.