As evidence that the recent brawling over digital music licences and listeners won't be for naught, ever-optimistic research firm Jupiter Media Metrix said yesterday that it expects the amount that can be earned from online music to grow to nearly £4bn in revenue by 2006.

In 2001 the number was a comparatively paltry £627m. The 2006 forecast includes revenue from CDs ordered over the internet, digital subscriptions and individually charged single downloads, Jupiter said.

This is good news for recent online music entrants such as MusicNet and Pressplay, which are hoping that their subscription services will take off soon. Jupiter has predicted that digital music subscription models will be the dominant digital-music format by 2003.

The researcher also predicted that subscription services alone will generate around £700m by 2006. Paid-for individual downloads will add another £418m million to online music companies' coffers that same year.

Of course, the extra cash will only fuel the music wars, as retailers and media companies face-off for market share, Jupiter said. The researcher also forecast that music subscriptions will look more like programmed entertainment, with added content and musical context to round out the services.

Although Jupiter is forecasting a music market worth £3.83bn in 2006, due to an overall slowdown in consumer spending the firm has had to revise a predictably rosy expectation released last July. Jupiter had forecast an online music market valued at around £4.32bn.