Microsoft has announced that Halo 3 has made more than US$300 million in sales in its first week on sale. The acclaimed Xbox 360 exclusive is the fastest-selling video game ever and already one of the most successful entertainment properties in history.

Microsoft says initial reports from retailers worldwide show console sales have more than doubled compared with the weekly average before the launch of Halo 3. "With games like Halo 3, BioShock, Mass Effect and Project Gotham Racing 4, Xbox 360 has the greatest line-up in the history of video games and the only console where consumers can play all of the year’s biggest blockbusters."

“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,” says Bill Gates, chairman of Microsoft. “Halo 3 embodies our vision for the future of entertainment, where some of the world’s greatest creative minds will deliver a new generation of interactive storytelling.”

Halo 3 is quickly staking its place as the most popular Xbox Live game in history with members gathering in record numbers to play on the world’s largest online gaming and entertainment network. 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. Within the first day of its launch, Halo 3 players worldwide racked up more than 3.6 million hours of online gameplay, which increased more than elevenfold to 40 million hours by the end of the first week, representing more than 4,500 years of continuous gameplay.

Since Halo 3 launched, gamers have unlocked nearly 30 million achievements. In its first week, Halo 3 drove a record number of Xbox Live Gold Memberships as hundreds of thousands of new members gathered online with friends, family members and other gamers around the world to collectively compete and complete the game.