Microsoft seems to have won another battle in the digital media war: Rival RealNetworks is licensing the Windows Media Audio software developer kit. Eventually you'll be able to play WMA files on RealJukebox, acknowledges Steve Banfield, general manager in the consumer division of RealNetworks. RealNetworks, founded by Microsoft alumnus Rob Glaser, already supports most audio formats with its RealJukebox. Windows Media has been the notable exception, and for RealNetworks, this is just another technology license. Microsoft cites the arrangement as proof of the universal adoption of the Windows Media format. RealNetworks joins more than 70 companies - including Yahoo, Lycos, AOL WinAmp, Sonique, MusicMatch, and Sonic Foundry - in licensing the Windows Media Audio tools, according to Microsoft. The company bolstered the announcement Tuesday with a Media Metrix report stating that last December, for the first time, the Windows Media player was used in more US households than any other multimedia player. "Windows Media is poised to be the universal format for digital audio on the Web," says Will Poole, general manager of Microsoft's digital media division. The format supports CD audio quality, a small file format, and built-in digital audio rights management. Rights management provides technology to ensure copyright protection and security for digital music. With RealNetworks on board, most jukebox software and major portable players will support WMA. Many major record labels, including Warner, BMG, and Sony, use WMA for its digital audio rights management. Microsoft hopes RealNetworks' support means WMA is catching up to the popular MP3 format. "The broad adoption of the Windows Media format means consumers can get the quality they demand on whatever jukebox or player they want," Poole says. "It also reduces the need to offer content in multiple formats." Microsoft pushes WMA to record labels because of the built-in rights management. But it's worth noting that software developers can license the technology at no charge, so it doesn't have to be their only choice. If record labels want to support several music formats, Microsoft's all-in-one package may make WMA less appealing. Some music publishers, like Universal Music Group, already license Intertrust's rights management technology. Intertrust's OpenRights Initiative is considered more flexible than WMA's rights management. OpenRights components are free, and may be used with other digital rights management, copy protection, or secure distribution systems. But Microsoft won't say whether it will license Windows Media technology to vendors who use other rights management tools. "We'll consider it at that time," Poole says. MP3 still reigns on music sites, but as record labels and artists seek ways to sell music rather than give it away, secure formats like WMA have added appeal. Analysts predict we'll have multiple digital music formats for some time, but for consumers, it'll all be the same digital tune.