With nearly six years of operational success both on a financial and managerial level, Valve’s digital distribution service Steam amassed a running tally of over 25 million accounts in 2009, up 25 percent from the previous year, the company announced today. At least 10 million of these accounts have involved themselves in social activities by creating a Steam Community profile. In addition, the peak number of concurrent online users eclipsed the 2.5 million mark in December, no doubt thanks in part to the Steamworks-powered juggernaut Modern Warfare 2.

More fun facts that further cement Valve’s lead position in the digital market can be had after the break. The service will have its sixth birthday come March and we wouldn’t be surprised if Newell and co decide to celebrate the occasion with more wallet-emptying sales.

* During the last calendar year the platform surpassed 25 million active accounts, up 25% from the prior year. Of the 25 million accounts, over 10 million of those have profiles in the Steam Community.

* In addition to the millions of new accounts created during the year, the peak number of concurrent users eclipsed the 2.5 million mark during the month of December, pushing Steam’s average monthly player minutes to more than 13 billion.

* Meanwhile, Steam now offers over 1,000 games from over 100 developers and publishers around the world. Unit sales for 2009 increased by more than 205%, marking the fifth straight year the platform has realized over 100% year-over-year growth in unit sales.

* 2009 also delivered a wave of titles supported by Steamworks, in tangible and electronic versions, including Call of Duty: Modern Warfare 2, Dawn of War II, and Empire: Total War. Empire also used Steamworks for the delivery and management of its paid downloadable content releases.

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