I just finished reading Omerta, it took me a while, and I was disappointed. It had none of the epic grandness that The Godfather or the Sicilian had. Puzo glossed over many details and the characters were pretty generic. The plot was standard mafia fare... nothing interesting or page turning. The ending was very anti-climactic too. I never feared for Astorre or any of his cousisns and didn't really care about one character in the book, outside of Rosie.
This is definitely Puzo's weakest.
However, I did like Rosie, the Sturzo Brothers and even Heskow. They were probably the best written characters and Aspinella Washington could have been a great character had Puzo devoted more time to her and made her a deeper character. Instead, she came off like an Indiana Jones or James Bond villain.
And then there were some Puzo sentences and images that captured his simplistic beauty and ease, but they were few and far between, IMO. Everything else was by the book bestseller jargon. And while Puzo has done his best writing as a commercial writer, I've always believed him to be better than that. With Omerta, he sank to commercialism.
I think a movie could be good, it could fix a lot of the book's flaws, but on the whole, I would like to see a better book be made into a movie. Omerta just doesn't deserve it.
** (out of ****)