i read it on tribalfootball as well as on fans fc....
but i think they've the rumour from tuttosport

...
anyway here's the article:
Juventus have an agreement with Arsenal skipper Patrick Vieira regarding a future move to Turin.
Tuttospot report today the only reason Juve have not signed the French international is that they have failed to find a buyer for Lilian Thuram.
However, Juve chief Luciano Moggi has an agreement with Vieira's representatives that the Turin giants will be his next club.