By way of number crunching from analyst firm Forecasting and Analyzing Digital Entertainment, otherwise known as FADE, Valve’s Steam service brought in nearly $1 billion last year — an estimated $970 million to be exact. Hit the jump for a breakdown of the top ten grossing titles, ranked by estimated revenue. Activision’s Call of Duty franchise is, perhaps unsurprisingly, leading the pack.

Top Selling Titles, by Estimated Gross Revenues in 2010
* Call of Duty: Black Ops (Activision) – $98.2 Million USD
* Call of Duty: Modern Warfare 2 (Activision) – $39.4 Million USD
* Left 4 Dead 2 (Valve) – $36.0 Million USD
* Battlefield: Bad Company 2 (Electronic Arts) – $25.4 Million USD
* Sid Meier’s Civilization V (2K Games) – $21.9 Million USD
* Portal (Valve) – $20.0 Million USD
* Fallout: New Vegas (Bethesda Softworks) – $17.0 Million USD
* Metro 2033 (THQ) – $13.4 Million USD
* Mafia II (2K Games) – $11.9 Million USD
* Warhammer 40,000: Dawn of War II: Chaos Rising (THQ) – $10.8 Million USD

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