Take2's latest financial results press release gives us some indication of Rockstar Games' plans for GTA IV. The release suggests that 'exclusive episodic content' (we have yet to decipher what Rockstar means by this) will be available for download in 2008. Both Sony and Microsoft are expected to have exclusive content for their consoles in GTA IV. Yet Take2's announcement seems to hint that perhaps the games will be identical on release, and platform-specific content will simply be made available for download in 2008 (months after the official release date). Or perhaps the games will be released with different content, and the additional content will be revealed for both platforms in 2008. You're free to speculate for yourselves about what it means. So from the horse's mouth:

"Grand Theft Auto IV, the next-generation console debut of the genre-defining franchise, will be shipped simultaneously for the Xbox 360 and PLAYSTATION®3 in October. Starting in 2008, Rockstar will introduce exclusive episodic content downloads for Grand Theft Auto IV."
Take 2 Games, February 28, 2007

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