there has been tons of complaining about the refs in serie A this season. I don't know if it's a hang up from calciopoli that's lead to everyone being suspicious or what but it seems pretty much every round has been followed by a barage of suspicions.
the milan penalty was soft, but I think it's being over-played a little because some of the clubs, fiorentina and inter most notably, have spent the whole season cultivating a victim complex.
that said, the refereeing has been poor in serie A, but some teams are shouting conspiracy when it suits them. fiorentina were given an incredibly soft penalt against milan just last month, and then the ref failed to give a clear handball penalty to milan in the last minutes. more consistency is needed bu it's swings and roundabouts.