Activision announced today that Call of Duty: Black Ops continues to set sell-through records crossing the $1 billion mark in sales worldwide since its launch in November, according to internal Activision estimates.

In its first five days alone, the game sold more than $650 million worldwide, outpacing theatrical box office, book and video game sales records for five-day worldwide sell through in dollars, according to internal Activision estimates and boxofficemojo.com. The game exceeded Activision's previous five-day worldwide record of $550 million set by last year's Call of Duty: Modern Warfare 2.

To date, more than 600 million hours have been logged playing Call of Duty: Black Ops since the game launched on November 9, 2010. According to Microsoft, the average player logs on more than once a day and plays for more than one hour each time. Over half of that time is spent playing online with and against friends, illustrating the unique social characteristics of the game.

Lawsuit Against former executives Also targets rival EA

In related news, Activision on Tuesday added rivel Electronics Arts (EA) in its lawsuit against two former executives. The company also put a price tag on its claim for the first time, seeking $400 million.

The complaint filed in the Los Angeles Superior Court follows the suit filled by two former Activision executives against Activision last March. They claimed that Activision fired them to avoid paying royalties for their work on the "Call of Duty" franchise.

In the complaint, Activision alleges that EA intentionally interfered with contracts, engaged in unfair competition and aided and abetted breaches of fiduciary duty by the executives.