VoIP provider Skype announced on Wednesday that it would open up its platform next week to allow its service to be integrated into Web sites and applications. After just two years in existence, Skype already claims some 51 million users worldwide.

Skype's goal is to create the largest instant messaging platform in the world, and says the move opens up the service to a variety of uses in gaming, e-commerce and communications tools.

But there's one catch: only the IM portion of Skype can currently be integrated into third party applications. The VoIP features of the client still require that a user run the company's messaging application.

No indication was given as to whether the company would eventually open up its VoIP service, although posts on the company Web log seemed to indicate it would not.

Despite increasing competition from the likes of AOL, Yahoo and now Google, Skype has seen some financial success, with over 2 million paid users. Those subscribers pay a per-minute fee to make outgoing phone calls, as well as a recurring charge for a telephone number that callers can call into.

"As we enter our third year in business and as the only company totally focused on global Internet communications, we think now is a perfect time to make these popular features available to anyone who wants to build community and communications into their website or applications," Skype founder and CEO Niklas Zennstrom said in a statement.

According to at least one research firm, Skype has nothing to lose. It accounts for as much as 45 percent of all VoIP traffic in the United States, and has experienced similar success elsewhere.

The company will make its SkypeNet and SkypeWeb APIs available through its developer program.