Yup, go back a little and you'll see some people discussing it.
On Vieira, I agree that he might not be precisely what we should look for if we are annoyed by Davids' behaviour.
I've seen him elbow players in the face without refs noticing and screaming profanitys at opponents (all part of a london-derby one might say, but not what we want if we are to avoid overly aggresive players).
If Vieira is what Juve is looking for then they might as well stick with Edgar.
Besides a little aggression isn't that bad, even though edgar is certainly borderline, Moreno Torricelli was one of my favourite players for juve (back when we still one european cups).