Is the publisher of "Guitar Hero" working on an online music store that could rival Apple's iTunes?

In an interview with the Financial Times, Bobby Kotick, chief executive of the recently merged Activision Blizzard, which publishes the franchise, said, "I don't think there have been a lot of credible alternatives to iTunes, but 'Guitar Hero' certainly has that potential."

Should the game creator actually make good on Kotick's musings, things could get interesting. The "Guitar Hero" franchise has already sold 20 million units and generated $1 billion dollars in revenue. Music publishers note that they receive a much higher percentage of that money when their songs are offered as downloadable content rather than on the original game disc.

For one, there is no end in sight of revenue generating spin-offs. "Guitar Hero: Aerosmith" and a Nintendo DS version called "Guitar Hero: On Tour" were both released at the end of June, while the sequel to "Guitar Hero: III," "Guitar Hero: World Tour" is set to come out this fall. Not to mention "Guitar Hero: Metallica" which is planned for early next year and the long rumored Van Halen version.

Should a music store come to fruition, however, would content bought on it be usable with different "Guitar Hero" games or would fans have to buy tracks for each version of the game? Activision's record is mixed on that score. Tracks downloaded for "Guitar Hero III" will be playable on the upcoming "World Tour" game, but they are not playable on the Aerosmith version.