For a monthly fee, starting at $9.95, RealOne Music users can stream or download tunes from the libraries of AOL Time Warner, Bertelsmann and EMI Group. Songs are then played over a personal computer. RealOne is the software downloaded by users.
More than 75,000 tracks will be available, including those by Christina Aguilera, Backstreet Boys, Eric Clapton, Faith Hill, Dave Matthews Band, 'N Sync, R.E.M. and Britney Spears.
But MusicNet has limitations that may make some users yearn for the free-for-all world of Napster.
CBS News Technology Consultant Larry Magid says the most important limitation is that "the recording industry controls where you can play, and a lot of people say 'If I pay, I should be able to listen in my car, jogging, in my living room - wherever I want.' But to say you have to listen at the PC - that will limit enjoyment that they have to pay for."
The basic fee covers only 100 downloads and 100 streams, though more credits can be purchased. Furthermore, downloaded music no longer works after 30 days, though it can be reactivated, but at the cost of a credit.
The music also can't be stored on a portable music player or burned onto a compact disc.
Subscribers can browse libraries alphabetically and by genre through the RealOne player, which is a free download. The program also will recommend related artists, much like how Amazon.com suggests books.
"The benefit to being a subscriber will be convenience and ease of use," said Mark Hall, vice president of programming for Seattle-based RealNetworks.
MusicNet is the first of two label-sponsored firms announced as the industry battled Napster, a file-sharing service that allowed users to swap tunes without paying. It went offline in July amid a flurry of copyright infringement lawsuits.
MusicNet also will be distributed through America Online Inc., though the availability and pricing have not been disclosed.
Napster also is supposed to become a MusicNet distributor once the company releases a version of its software that honors copyrights.
The other major-label service, pressplay, is owned by Vivendi Universal SA and Sony Corp. and will use Microsoft Corp.'s Windows Media Player.
Unlike MusicNet, pressplay will let users accumulate songs and continue to listen, provided their subscriptions are paid. It also will not allow CD burning or listening away from a PC.
The service's pricing and other details will not be revealed until its launch, expected sometime before Dec. 21, said Seth Oster, pressplay's spokesman.
Neither service will include all the music from the partners' catalogs because the labels do not hold all the digital distribution rights. More tracks will be added as deals are renegotiated.
Though Napster has been offline for months, Napster-like services contine to flourish on the Internet. The research firm Webnoize recently reported that the use of Grokster, Kazaa and MusicCity increased 20 percent between September and October.
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