Initial reports from retailers worldwide show that Xbox 360 sales have more than doubled compared with the weekly average before the launch of Halo 3.
"Halo is truly a cultural phenomenon, and the launch of Halo 3 is an important milestone for Xbox 360 and for video games as entertainment and as an art form," said Microsoft chairman Bill Gates.
More than 2.7 million gamers played Halo 3 on Xbox Live in the first week, representing nearly one third of the seven million Xbox Live members worldwide.
Halo 3 players racked up more than 3.6 million hours of online gameplay on the first day of its launch, which had increased to 40 million hours by the end of the first week, representing more than 4,500 years of continuous gameplay.
The game has also driven a record number of Xbox Live Gold Memberships as hundreds of thousands of new members gathered online with friends, family and other gamers around the world to collectively compete and complete the game.
The record week-one sales follow previous announcements of $170m in sales in the US within the first 24 hours of release.
More than 1.7 million copies of Halo 3 were pre-ordered in the US, surpassing the previous record-setting pre-sales of Halo 2 and making it the fastest pre-selling game in history.
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