Apple's iPhone may be open to developers now, but don't expect to see Microsoft bringing its Flash competitor Silverlight to the handheld any time soon. CEO Steve Ballmer shared that tidbit during the MIX 08 conference in Las Vegas on Thursday, according to Computerworld.

Silverlight is Microsoft's multimedia platform designed to compete with Adobe's ubiquitous Flash. Like Flash, Silverlight is available for multiple operating systems and Web browsers. Unlike Flash, however, it does not share the same popularity.

One concern Mr. Ballmer voiced was over the 30 percent cut Apple will take from applications sold through the App Store, Apple's distribution system for iPhone and iPod touch applications. He commented "It sure seems like they're trying to charge a whole lot more money for it," and added that he was concerned Apple might charge a 30 percent fee for distributing an iPhone version of the free Silverlight.

While Apple CEO Steve Jobs did confirm during its iPhone SDK and enterprise road map event on Thursday that the company will take a cut off the top of every application sold through the App Store, 30 percent of nothing is still nothing, making the fee affordable even for Microsoft.

"Maybe Apple isn't welcoming open and royalty-free runtimes on [the iPhone]," Mr. Ballmer said.

Apple made it clear that the only programs it would block from the App Store included porno applications, malicious apps and programs that threaten user privacy.

Microsoft's lack of interest in bringing Silverlight to the iPhone will likely disappoint a very small handful of users, but not nearly as many as are lamenting the lack of an iPhone-native Flash player.