Call of Duty: Black Ops reaches $1billion sales mark

Call of Duty: Black Ops has broken the $1 billion (£647 million) sales barrier, figures show.

Sales results released by publisher Activision Blizzard suggest it took just six weeks to do it.

In doing so it joins an elite group of entertainment releases to reach the billion dollar mark.

Others include Michael Jackson's Thriller album and James Cameron's 1997 hit film Titantic.

Activision CEO Bobby Kotick said: "Only Call of Duty and Avatar have ever achieved the billion dollar revenue milestone this quickly".

Fans of 2010's biggest video game have reported connectivity problems in recent weeks though.

Players of the PS3 and PC versions complained about being booted from games, freezing and connection error messages.

Developer Treyarch released two patches to fix the problem.

'Unprecedented'

Activision's Eric Hirshberg said: "Even more remarkable than the number of units sold is the number of hours people are playing the game together online."

Call of Duty: Black Ops was released in the UK on 9 November

According to Activision, more than 600 million hours have been logged playing the game since its worldwide launch.

Microsoft says the average fan using it on Xbox Live logs on more than once every day and plays it for one hour at a time.

Black Ops is the 7th in the hugely popular Call of Duty series, the third developed by Treyarch, and takes gamers on a series of Cold War adventures.

There are high expectations within the video games industry that it will surpass the success of its 2009 predecessor.

COD: Modern Warfare 2 sold more than 20 million units around the world meaning it too joined the exclusive one billion dollar club.

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