Napoli will be Juve's main contender. Mazzarri has taught Inter how to play counter attacking football, and they seem to be rejuvenated with a new coach and a fresh start, but teams will find them out sooner or later, and their squad isn't really one to write home about. IMO Napoli have the better individuals, the better coach, and a core who have played together for a long time now ( Cannavaro, Zuniga, Inler, Maggio, Hamsik)