Continuity mistake: When the SWAT team are inside the mansion, Logan jumps down to save Rogue Bobby and John, and he chucks two guys back some distance. In the overhead shot, the four SWAT guys are together on the floor, instead of two of them being some distance away like we saw in the previous shot. (00:38:25)The-Immortal
Continuity mistake: In the museum scene at the beginning when Iceman freezes the guy on the floor, you can see a guy standing beside him with jeans and red boots on. The shot goes back to the guy on the floor and the one who was standing beside him is now standing behind him. (00:09:50)The-Immortal
Visible crew/equipment: Right after Cerebro begins to kill all the mutants, Mystique gets down on her knees in pain and tells Magneto to hurry. The next scene is a shot of Stryker running down a corridor and opening a door to go outside. Before he opens the door, you can see the shadow of a crew member going across the door.
Continuity mistake: When Xavier is in the plastic prison with Magneto, at the end of this scene, you see Xavier put his hands on the doors of the prison, but in the following shot from outside the prison his hands have changed positions on the doors. (00:33:10)The-Immortal
Audio problem: When Bobby's brother dials 911 you hear 3 tones (for the 3 digits he dials). But the 3 tones aren't the right tones you hear when you dial 911 from a touch tone phone. In fact the 2nd and 3rd tones should be the same because it's the same digit but they were different. As if someone just dialed 3 random digits. And there's no doubt he dialed 911 because the operator answers "911". (00:56:55)
Revealing mistake: In the beginning of the movie when Wolverine puts the cigar out in his hand, you can see the mark of a wedding ring on his ring finger (Hugh Jackman is married). Even if Wolverine got married during the "blurred" bit of his memory so doesn't remember it (tenuous at best), his healing ability would have removed any ring mark. Either way it just doesn't belong. (00:19:50)
Revealing mistake: In the part where Mystique (as Grace) and the guard are in the bathroom, right after the guard drinks the rest of the beer and passes out, Mystique turns him over and you can see the guard move his right leg to steady himself even though he is supposed to be knocked out. (00:47:00)