Call of Duty: Black Ops sells 20 million - Analyst

Call of Duty: Black Ops--the best-selling game in the US of all time--shipped in November and has minted over $1 billion to date for publisher Activision. Now, an analyst is trumpeting a new sales milestone for the game.

According to a recent tweet from Wedbush Securities analyst Michael Pachter, Call of Duty: Black Ops has sold 20 million units, 12 million of which were Xbox 360 copies. It was not made clear if the figure represented global sales or the tally of one specific region, and attempts to reach Pachter for comment were not successful.

The last officially reported sales total for Black Ops came in March, courtesy of the NPD Group, which said the period first-person shooter had sold 13.7 million units in the US alone.

Yesterday, Activision released the second $15 downloadable content for Black Ops in the form of the Escalation add-on, which Pachter estimates sold 4 million units on day one. The pack bundles four new multiplayer environments and one new zombie level dubbed "Call of the Dead."