There is another difference that I just noticed when I listened to the book on tape recently. In the movie Vito is given the name Corleone by the clerk at Ellis Island. He mixes up the last name and the town and all of a sudden Vito Andolini becomes Vito Corleone. In the book he takes the name of Corleone as a means of maintaining a connection to his past.
"After all, we are not communists"
Christopher Moltisanti: You ever think what a coincidence it is that Lou Gehrig died of Lou Gehrig's disease?
Tony Soprano: Yeah well, when you're married, you'll understand the importance of fresh produce.
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