I know that Cannavaro left us in our greatest plight ever, however, I've had nothing against him. Yes, I don't consider him my heroic defender anymore as in the past couple of seasons, even though, I don't blame him that much for leaving us. At the end, he wasn't like Zambrotta for example, who spent 7 years in Juve and with the first fall, he left.
Furthermore, Cannavaro has stated more than once that he respects Juventus and he wished the best for us.
By the way, what I've just said has nothing to do with my opinion about him to return or not. Generally, I prefer young promising defenders like Criscito and a world-class defender between 25 and 30.