Wedbush Morgan analyst Michael Pachter believes that Rockstar has delayed the release of Grand Theft Auto IV because it is struggling with development on the PlayStation 3. And since it's likely that Rockstar had an agreement with Sony not to favour one console over the other, it means they can't release one version and delay the other.
"We think it is likely that the Rockstar team had difficulty in building an exceptionally complicated game for the PS3, and failed to recognise how far away from completion the game truly was until recently.
"We think it is also likely that Take-Two had a contractual commitment to Sony that it would not favour competitor Microsoft by launching the Xbox 360 version of GTA IV prior to launching the PS3 version, and believe that any delay of the PS3 version necessitated a delay of the Xbox 360 version."
The game has been delayed until February, March or April of 2008, though hopefully we'll have a more specific date soon.