Are you serious? Have you even watched some of the lineups fielded by Mourinho. Remember 5 -0 to Genoa when they had like 1 striker? The difference between Inter and Juve is clear. It's not injuries, it's the squads and coaches.
Inter are simply better. They have a better defense which they upgraded in the summer, whilst Juve added a world champion, Cannavaro. Whoop-de-do. They have better full backs. Maicon > Zebina, Grygera, De Ceglie, Grosso.
Juve may have purchased more "attractive" signings this summer but so far Diego has been a non-factor save like 3 games. Has he even made 1 through ball to a ST that lead to a goal yet? Sneijder was supposed to be a Madrid reject that wasn't supposed to be even worthy of cleaning Diego's shoes, yet he's proved to be the perfect replacement for the camel faced choker. Add Milito and Eto'o to the fray and Julio Cesar and you have the perfect unit for this league. Injuries of other clubs have nothing to do with it. Do you think Jose would have been 2-0 up against Napoli at home and lost? Ciro is young and inexperienced and that's Juve's problem. Jose manhandled Leonardo due to this and will do the same to Ciro for the same reason. You can't expect to win a league with such a young coach.