Not everyone involved with the original films is involved--or even pleased. Director Francis Ford Coppola objected to the game adaptations of his Godfather films, saying, "They use the characters everyone knows… and then for the next hour they shoot and kill each other." Sadly, Coppola's comments cut to the heart of the matter: The adaptations in question will most likely be simple, "videogamey," shoot-em-up shadows of their film progenitors. While the designers of these games will certainly pick up on the tangibles of their cinematic sources--the characters, settings, and events--they seem to be ignoring the more subtle (and important) themes, pacing, and psychological tension that are at the cores of the original films. Scorsese's Taxi Driver, despite its harrowingly violent climax, isn't about vigilante gun battles so much as it's about the protagonist's mental turmoil and urban alienation--and those are aspects that a simple Grand Theft Auto clone can't hope to translate.
With the immensity of these classic movie licenses and the profit-focused mindset of publishers like EA Games (who are behind the virtual-Godfather), the designers of these games can't afford to take chances, to the detriment of the games themselves. Action sells, but when approaching subject matter that's this important, developers need to go out on a limb and address the aspects of these films that really made them resonate with viewers--or just leave well enough alone.