I hated Mafia. It was a snore fest from the beginning. Maybe if I stuck it out longer it would of gotten better, but it just didn't have a that fun factor I feel in so few games.
Personally I found GTA3 to be amazing right to the end, and the reason I put down close to $400 for a new video card. Which only fueled my urgancy to play Vice City which was also stellar. Now I'm just waiting for Activision to release Streets of LA on the PC, and Driver 3.
Too bad for some obscure reason neither Vice City or GTA3 will run on my system anymore. I'm going in to withdrawl.

Maybe I'll see if I have a copy of Mafia somewhere and give a second go.
The one thing that I found the most annoying about Mafia was that you have to keep your speed limit or the cops would come, and the cars initially sucked ass as for control and speed.