Marco should be so proud of reaching the semi, and even prouder of how he played the first set. He was going for it and hitting lines. The point that broke his resistance was the set point that he had - Federer came up with the backhand pass and that was that. I hope he keeps rising in the rankings.
As for Roger, I think he was passive often, but then again Chiudi was coming up with penetrating, hard shots - Fed forced on the defence. He played the big points really well though; like when he saved 3 consecutive BPs and of course saving that SP.
The two things I'll remember from this match is Chiudi's inspired display and Roger hitting 4 consecutive blasting forehand winners to win a service game in the first set. (I think it was four anyway.)
Good luck against Nole.