I don't know how anyone can say Zidane isn't a Juve legend. He won two FIFA World Player of the Year awards and was in the top three once more, 1 Ballon d'Or, 3 Onze d'Or, and a World Soccer Player of the Year award while with Juventus. With the team he helped us to 2 scudetto, 3 cups, and we were runner ups in 2 Champions Leagues. The way some fans have been talking about Zizou you'd think they were Inter supporters talking about Ronaldo. It's not like he screwed the club over or anything when he left. He left because he had accomplished all that he felt he could in Turin. It didn't look like Juve was going to win a CL, which was the only thing left for him to do. Besides that it got us €66 million in spending money. Baggio left for no good reason really, and only got us a UEFA cup. Yeah he wasn't as loyal to the shirt as Del Piero is, and his legacy isn't as tied up to the club, but Zinedine Zidane is the greatest player to have ever put on the black and white.
On a side note, he had more appearances with Juventus than Platini or Baggio; he only had 15 fewer appearances with the old lady than Trezeguet has so far, and Trez is probably leaving this summer(he would have left already if he had his way).