The digital content distribution industry will continue to innovate and change, experts agree.

One future incarnation of music downloads could let users swap digital content legally, with people legally trading music links, not files.

The Content Reference Forum (CRF) is a group promoting new technology devised by Universal Music Group and Microsoft. Once Internet users click on a link to a piece of music, the technology determines what kind of device the requestee has, and permits them to listen to a song for free for a period. If they like it, then they can buy it.

EMI Music is also considering using file sharing in the next few years to promote its artists, according to Business Week. That company has already reached a deal with innovative legal peer-to-peer service Wippit in the UK.

Business Week believes the Internet is opening up plenty of ways to reach wider audiences and that file sharing may become a key way that Web users discover new music.

For example, (not the Apple software) uses listener ratings to pinpoint appealing bands from among the 200,000 independent musicians who post songs on its site. Thirteen of these bands have now signed with labels. CEO Ali Partovi said: "We're developing a new model that takes advantage of technology to do a better job of discovering and promoting music."