Having gained a stable subscription revenue base from World of Warcraft, Activision Blizzard may look to monetize some of its other titles through subscriptions -- like Guitar Hero, CEO Bobby Kotick said today. Activision Blizzard beat estimates to the tune of $711 million in revenues for its first quarter as a combined company, the company revealed today. Anticipating investor concerns about an uncertain economy, president and CEO Bobby Kotick reassured them on the company's results call that stable subscription revenue from World Of Warcraft "gives us advantages over many of our competitors -- especially as we enter the holidays." And Kotick added that the just-launched Guitar Hero: World Tour's song creation utility's early success might end up as a new revenue source. Kotick says that there are now 25,000 user generated tunes that have been created for the game, and projected "up to 100,000 songs" by the end of this year. "The ability to offer these songs on a subscription basis may very well result in the newest subscription opportunity in our portfolio," he said.