During an interview with Next-Gen, Aaron Greenberg, director of product management for Xbox 360 and Xbox Live, claimed that Microsoft was informed by its retailers that the Xbox 360 version of GTA IV is outselling the PS3 version by a margin of two to one.

However, there are no official figures that could confirm Greenberg’s comment.

When Next-Gen asked a Sony rep to comment on Microsoft’s findings, he said that the situation doesn’t line-up with what the Japanese company heard from the retailers.

Nevertheless, the Sony official declined to make any other comment until the figures compiled by NPD will be released. 

Another Sony official expressed his believe that GTA IV will drive PS3 sales, but he didn’t get into details

"Grand Theft Auto fans who love the game grew up on PlayStation and we believe that rich heritage will be a deciding factor for many gamers at retail," assured PSN big wig boss Peter Dille, quoted by Play.tm. "This enthusiasm for GTA IV, combined with the excitement behind Gran Turismo 5 Prologue, Metal Gear Solid 4, LittleBigPlanet, and Resistance 2 will further drive PS3 hardware sales."

Sincerely, I doubt that Xbox 360 outsold Sony in such a manner. So far, the only third-party figures that are available about the GTA IV sales are coming from the UK, compiled by the research company ChartTrack.

According to their findings, Xbox 360’s GTA IV outsold the PS3 version, but the sales were very close: 335,000 versus 274,000.

I find it hard to believe that Xbox 360 will do very differently in the rest of the world. Still, the situation in the United States could be somehow different because in Europe Sony has introduced a GTA IV PS3 bundle that could be also responsible for the strong sales of Sony’s gaming platform.

In the first day of GTA IV availability, Microsoft was very quick to remind gamers that Xbox 360 will benefit from the additional content promised by Rockstar for Xbox Live.

According to Microsoft, the new content will be available starting this autumn, but the company did not release any other details. It only said that it will add “hours of gameplay.”

Speaking of Xbox Live, Greenberg revealed that GTA IV is already a smash hit on Microsoft’s online service. In the first day of GTA IV madness, close to 1 million GTA IV users went online with the game on Xbox Live, which means that the game has established a new record, knocking off Halo 3 and Call Of Duty 4.

Analysts have predicted that GTA IV will earn $400 million during its first week, which means close to 9 million units sold.

GTA IV is not only a box office hit, but it has also earned top grades from the gaming critics.

For example, GameRankings.com, a website which compiles a general score based on the reviews written by the biggest gaming sites, has calculated an Average Ratio of 98.7% based on 29 reviews. The PS3 version of the game has achieved an Average Ratio of 99.6% based on 16 reviews.

With these rankings GTA IV has scored a new record, topping the Best Games List at GameRankings. It has dethroned the previous record holder, The Legend of Zelda: Ocarina of Time, which had an Average Ration of 97.6%.