Call of Duty: Black Ops has broken day one sales records, moving more than 5.6 million units in the US and UK alone. In doing so it has beaten previous title holder Call of Duty: Modern Warfare 2, which sold 4.7 million units on its first day.

The sales have generated $360 million for Activision compared to Modern Warfare 2’s $310 million.

In a statement, Activision CEO Bobby Kotick said, “There has never been another entertainment franchise that has set opening day records for two consecutive years and we are on track to outperform last year's five-day global sales record of $550 million.

“The game's success underscores the pop culture appeal of the brand. Call of Duty: Black Ops is the finest game that Treyarch has ever made and raises the bar for online gameplay by delivering the deepest and most intense Call of Duty experience yet.

“The Call of Duty franchise has over 25 million players around the world that are engaged in billions of hours of online gameplay, and we are committed to supporting them with new content and features on a more frequent and regular basis.”

Gameplanet's Dan Cheer has reviewed Black Ops for both Xbox 360 and PC. He determined that Black Ops on Xbox 360 is a sound if not particularly innovative instalment in the franchise. Of the PC edition he said, “In its current form, there are simply too many issues to recommend Black Ops,” with the caveat that developer Treyarch is likely to address these issues with a patch in the near future.