The Mac maker has scheduled an event for next Thursday at San Francisco's Moscone West convention hall. "The year's biggest music story is about to get even bigger," Apple said in an invitation to journalists.
The company is expected to launch the long-awaited Windows version of the iTunes Music Store at the event, according to Wall Street brokerage Needham. Apple earlier said it would release the Windows service sometime before the end of the year.
Needham analyst Charles Wolf estimated in July that online music stores in the United States could generate $3 billion in annual revenue, assuming they can capture 15 percent of the free file-sharing market. Wolf projected that Apple could claim 20 percent market share, giving it a potential yearly revenue boost of $600 million. Apple said last month that it hadthrough the iTunes store.
Still, even those optimistic about the market don't see Apple getting a major boost to the bottom line.
"At a profit of less than 10 cents per song, the music store does not represent a major income opportunity for Apple," Wolf wrote in the July report. Still, the company could benefit from increased iPod sales, he said.