During Microsoft’s Tokyo Game Show press event, the publisher announced that its recently released Halo: Reach managed to accrue $200 million in worldwide sales during its first day of availability.

The Xbox 360-exclusive first-person shooter launched around the world on September 14th (and 15th in Japan), and apparently, somebody actually bought the game!

While it’s difficult to calculate exactly how many copies were sold from that number alone (due to pre-orders and all of the different versions of the game), it would work out to roughly 3.3 million copies of Halo: Reach making its way out to the world on day one. Specifically in the UK, Halo: Reach has sold over 300 000 copies.

Those are some large figures, and according to Microsoft, that $200 million mark represents the highest grossing entertainment product released this year, be it a game, movie, book or anything else.

Additionally, Halo: Reach broke the record for the highest number of simultaneous Xbox LIVE users, previously set by Halo 3.

Call of Duty: Black Ops has got some big shoes to fill when it releases on November 9th, and with some hefty fighting words coming out of Microsoft’s executives, Activision will be sure to try and bury the numbers set by Halo: Reach.