Nick @ PS3Center writes:
Team ICO's previos games, ICO and Shadow of the Colossus, launched on very different release schedules. ICO hit the US in September 2001, Japan in December, and Europe late in March of 2002. Shadow of the Colossus came closer,with the game hitting Japan and North America in October 2005 but it's trip across the pond was delayed 4 months further.
With The Last Guardian, Ueda aims to get the game out worldwide, simultaneously.