According to Yamauchi, Gran Turismo 5 Prologue will be receiving an update in the near future that will add more cars, more tracks and new features to the game. He also said that the full version of Gran Turismo 5 may not be released until 2010.
He also talked a bit about the oft-delayed PSP entry Gran Turismo 4 Mobile (which was first announced at E3 2004). Yamauchi said that the game was still in development, but that it would not be released until after Gran Turismo 5. Which means the game won't be out until 2010 at the earlist. Considering that it was one of the first PSP games announced, that's quite a delay.
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