12 cards

the other 4

Heinze tackles De Rossi. De Rossi cries out, holds his leg as if it's broken, Vassaras books Heinze. Rewinding it a couple of times showed Heinze didn't even touch De Rossi. De Rossi - an experienced player - knows exactly how to fall and how to look hurt.
Tonetto tries to stop Drenthe. Drenthe is quick, Tonetto gives him a push and touches the face of the Madrid sider. You can see Vassaras grab his whistle and blow. That is it. Then he sees Drenthe cry out, hands to his face and only then Vassaras pulls a card.
Vassaras books if the hurt player's show is performed well.
And he seems to whistle when he doesn't know what happened.
And he almost never gives advantage when the game needs it. A referee can show a card later on, does not always have to whistle when something happens.
Two more cards (Taddei, Guti) were also for minor fouls followed by great tumbling acts. These are good players, who know all the tricks.

3

Rules are rules. Questioning the referee's decisions - be they right or wrong - is not allowed. Still, a referee can choose not to book. Vassaras never does that, he does not question his own decisions.
And if you are frustrated and angry because your team is loosing and nothing seems to work and you hit the ball with a hand, you get booked as well. Most referees would warn a player the first time.

the 4 right ones

De Rossi even agreed when the ref booked him. Pepe didn't but Vassaras was right. Twice. Aquilani's card was the fourth right one.

58

A referee who sees 58 fouls has to look back at the match and wonder if it could be him, not the players. This is not the first time Vassaras has been whistling almost every minute of the game. Vassaras is up there with Mike Riley and Alain Hamer, notorious for finding fouls in almost every move. (Merk, the great man himself, once awarded 65 free kicks in a match between Juventus and (again) Real Madrid.)
Vassaras added 4 minutes stoppage time, mostly because he took so much time whistling and showing cards. Those 4 minutes were used by Roma to stall (Vassaras had no answer for that, he lost control for a while) and score another goal.

and

I like Raul, but his goal was off-side.