We"ll have to wait for monthly NPD Group data for hard sales figures, but the percentages are still notable.

Microsoft"s marketing blog Gamerscoreblog said sales of Xbox 360 rose 54 percent week-over-week as a result of GTA IV"s launch. The official blog also cited retailers who said that about 60 percent of GTA IV sales in the first week were for the Xbox 360 version.

Retailers said about 40 percent of new consoles sold with a copy of GTA IV, reflecting a strong attach rate.

The game has also been dominating Xbox Live, with over 2.3 million people playing GTA IV over the online service. It"s been the number one Xbox Live game since its launch.

It also drove 1 million concurrent users on Xbox Live this past weekend. Gamers have unlocked over 12 million achievements and 100 million Gamerscore points in the title.

GTA IV players also set a new record for time played, averaging four hours of GTA IV gameplay while connected to Xbox Live in the first week.