Steam Games parent Valve announced today that they had crossed the 15 million member mark.

Valve® today announced that Steam®, a leading platform for PC games and digital entertainment, has surpassed 15 million accounts and realized year-over-year sales growth of 158% through the holiday season. The year also marked the debut of the Steam Community and launch of several best-selling and critically-acclaimed titles such as Call of Duty 4, Bioshock, and The Orange Box. Throughout 2008 more Community features will be introduced to support existing games as well as new titles such as Valve's Left 4 Dead.

It's a short announcement but worthy of reading. Head on out.