Corrected entry: When Frank shoots the guy on the streets he is dead as a dodo on the floor with a big crowd around him. When Frank walks back to the cafe no one is there on the corner and the actual man Frank gunned down is seen walking away.
Revealing mistake: Frank pulls up to his buddy's house where he's offered a bribe of a ski chalet. When he gets out of the car there are visible snow flurries. The scene moves to the living room that overlooks a lake. The trees are all lush and green in the background - obviously not winter.
Suggested correction: That was Richie, not Frank, who was offered the bribe.
Continuity mistake: When Russell Crowe and the other cop are chasing a crook through a hotel room, Crowe gets pinched in a doorway by the crook with the door. The crook starts to bite Crowe's hand, so Crowe signals the other cop to smash the crook's head through the door with a mallet. When the cop does, he uses the handle end, and in the next shot, when he's pulling the mallet out back through the door, it's coming out with the hammer-head end first.
Suggested correction: This is incorrect. The mallet goes through the door handle first, then the door opens and we see the mallet end.
Correction: There is Tango's bodyguard who is seen before the shooting, wearing the same style suit and haircut. He is the man seen walking off after the shooting, not Tango. Crowds of people do not stick around after a shooting to be questioned by police.