I was going through the forum in Gamefaqs and in the forums of Platinum Games (creators of the game) and they said they are using the time waiting for the US/EU release to address the issues present in the PS3 version of the game !
I can't guarantee this is confirmed, but it came from too sources, and a guy received an e-mail from SEGA saying they are working on the game, so if you didn't import it, like me, chances are you'll get a better product !