Well... at some point I realized: I don't think I ever finished the book back in the early 90's. I'm glad I finally got to it, I've finished it. All is well.
I'm assuming that the book was so much like the movie, I kind of didn't see the point and moved on. And yet, I figured out why I thought I'd made up a scene from the movie in my head because there it was in the book. So... not exactly a 1:1, but pretty close. Until...
Once you get to a certain point in the novel, it diverges mostly in how much additional content is there. Like, Johnny Fontane is a major character, as is Lucy Mancini, and there's a whole storyline in Hollywood and Las Vegas that is interesting but was easily cut out to keep the movie focused on Don Vito and Michael's more compelling stories. The reason the Fontane stuff is there seems to be two-fold. (1) It's a reminder of the Don's far-seeing view and his ability to manage and manipulate things with a single move, and (2) pretty clearly Puzo was no fan of Hollywood and he wanted to do it dirt.
