Well those of you in the US may know all about having your hopes dashed, seeing as the game is essentially broken. Gamers popping in their shiny new Prototype discs are being told they don't have enough hard-drive space to install the game. Even when they do.
An annoying "fix" has been clarified by Activision which has been reported (rather ironically) by Joystiq: change the amount of free hard disk space on your system by 700MB. This can be done by either installing another PS3 game (like Infamous), downloading game demos (like the Infamous demo), or downloading and removing videos from the hard drive (like videos of Infamous).
Activision say there's a patch on the way so hopefully everyone will be playing Prototype on their PS3 as soon as possible.