Ubisoft's Assassin's Creed has shot to the top of the UK all-formats charts and become the second fastest-selling new IP on an individual format behind 2002's The Getaway.
The Xbox 360 version of the game claims 67 per cent of sales, with the PlayStation 3 version taking the remaining 33 per cent. It also becomes the third fastest-selling Xbox 360 game within a weekly sales period.
Last week's number one, Activision's Call of Duty 4, has been knocked from the top as it suffers a 33 per cent fall in sales.
At number three this week is EA's The Simpsons Game, taking a 9 per cent dip in sales, while THQ's WWE Smackdown Vs Raw 2008 is at number four.
Nintendo's new entry Super Mario Galaxy only manages to debut at number five but becomes the fastest-selling Wii game, with Dr Kawashima's Brain Training staying at number six following a 62 per cent climb in sales.
Electronic Arts' FIFA 08 slips to number seven this week, whle Disney's High School Musical: Sing It! leaps into the top ten at eight with a massive 170 per cent boost in sales following a release on the Nintendo Wii.
Konami's Pro Evolution Soccer 2008 is down to number nine and More Brain Training from Dr Kawashima sits at number ten.
The only other new entry in the top forty this week is EA's PC-exclusive Crysis at number 14.