I thought I bought Godfather II, but the clerk f'ed up and put Godfather I in the case.
It's ugly as hell, in terms of the environment. The people and cars are okay, but the world is uglier than GTA III. The voice acting is very good, with the real James Caan and Robert Duvall, and even a decent Marlon Brando impersonator. For its age, the cutscenes facial animation is pretty good, but the camera work and sets are just abysmal.
The shooting is pretty fun: there is lock-on, but you really want to sub-target in order to put someone down with minimal ammo use and quickly.
There is also a robust melee mechanic which is, sadly, mainly used against defenseless shopkeepers. You can jab, hook, threaten, Drag them around, drag them up off their knees, slam them into walls or desks, throw them over railings or off roofs... It reminds me a bit of Bully's fighting, except the bad guys will start shooting me while I'm still trying to be all pugilistic.
There is a protection racket game in addition to the storyline missions. I'm finding them pretty compelling. Rival gangs stand guard at businesses they control. Take them out so the shop owner can be approached. Each shop owner has a weakness, such as threats or violence or being shaken around; exploiting that weakness leads to higher payouts. Many shops have Rackets which can also be co-opted.
Anyway, it's surprisingly fun. I wish I'd played it earlier, when the graphics wouldn't be such a standout eyesore.