Rio Mavuba is a very good option at DM. He is still young and needs to develop. I would be all for a move for him to Juventus, but as a backup, not a starter. I have been really watching for DM's the past few months and I have concluded the following.
In order:
M. Diarra
Gilberto Silva
T. Frings
A. Diarra
R. Mavuba
I dont like Sissoko at all I think he is a moron.
I don't think that Juventus will go for a player like Mavuba. Between Paro and Marchisio we have to developing players and although Mavuba may have a better skill set than the afore mentioned, he might be an unneccessary signing. I would like to see a proven entity like Gilberto Silva, M. Diarra or Frings play next to Zanetti. My preference would be M. Diarra. I think the guy is a beast. Gilberto Silva is older, but would be perfect on Juventus. Frings is a good option too, but I fear that he is too aggressive for the role we need him to play.
If we are going to pick a young DM, even though he is 25, I would like to see us go after Alou Diarra. He is ready to start, huge, and played well for France in the WC final vs. Italy. He would be a solid pickup IMO.
As I said, I think if we acquired Mavuba, he would be a rotating backup with three other youngsters. I like him and wouldn't oppose him comming here, but I don't think he is what Juventus needs at the moment.