Global mobile payments provider Zong has been steadily growing its business helping online games players purchase the virtual goods and services by billing the purchase to their monthly phone bill. Today, the company announced a new milestone: it has processed payments for over 10 million unique users so far during 2009. To put that in perspective, the company has handled payments for a total of 25 million uniques since 2000.

In addition to this new milestone, Zong also announced its expansion with several new carriers in more countries in Eastern Europe, Russia, Southeast Asia, and South America. Zong’s mobile payment platform is now available in 30 countries through over 100 carriers, and is reported to be one of the strongest performing mobile payment solutions for many social application developers we talk with. The company also recently announced partnerships with online game publisher Outspark and teenage virtual world Gaia Online.