card trick

penalties

Yes, sure, a real foul and a hand ball, the former was obvious, the latter needed some complaining to the extra ref. This is one of the advantages of having that many refs: more people to complain to.

cards

Luisao kicked and pulled Torres from behind, Eriksson pulled his yellow card - he could have pulled a red. Then Liverpool striker Babel joined the discusion and pushed Luisao in the face. Do that again, Luisao seemed to be saying and Babel did it again. Luisao pushed Babel back and Eriksson - who had put his card back in his pocket - stood between the two who were yelling at each other. Then Eriksson pulled his card again and showed it to Luisao, Immediately after that he got a red one out and showed it - to me it looked like he showed it to Luisao: his second yellow thus a red - but it was to Babel, who had to leave the field.
Of course all this didn't show on the match report. It made no sense to me.

referees

more referees cause chaos, especially when those extra referees are centre referees themselves.