The research firm also said that the digital music player market is set to expand from 37 million users this year to 100 million users in 2011.
Apple shows no sign of losing momentum, said Michael Gartenberg, vice president and research director at Jupiter Research. This is mainly due to its conditioning of customers to expect and adopt regular upgrades.
"Despite the coming of Zune, the return of closed-loop digital music service-device combinations, and music phones on the horizon, the iPod should not lose significant market share in the next 12 to 18 months," said Gartenberg.
Mobile phones capable of playing songs to MP3 quality present the biggest growing threat to digital music players, Jupiter Research said. The number of phones that fit that bill will surpass music devices in quantity by 2009, the firm reports.
David Card, who led the analysis in the report, calls impulsive over-the-air music purchases "a tough challenge" both for wireless devices and phones thanks to issues with infrastructure, compatibility, pricing and user interfaces.
"US mobile phone carriers are under-emphasising, or ignoring altogether, the necessity of enabling users to 'sideload' existing music collections onto a phone because they can't charge for it," said Card.
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