Continuity mistake: When Magneto lands the Golden Gate Bridge on the island, as it hits land it is still very light. When the Brotherhood start to walk toward the island, it cuts to a wide shot of them still walking on the bridge, and it's suddenly dark.
Visible crew/equipment: When Lois pulls up to the house where the blackout was traced to, she hears some music coming from the boat down at the dock. As the camera pans upwards over the car, as she steps out, the whole camera and a crew member are reflected in the side of the car.
Continuity mistake: At the end, during the fighting in the Cathedral, the last woman left is getting first cut by Steven Seagal at the right breast. A moment later, her cut is on her left side. The next moment it is on the right side again.
Factual error: In a few scenes at the hotel by Heathrow Airport, several British Airways aircraft are seen, all with the current paint scheme instead of 1995's.
Audio problem: Just after the car crash, when the zombies are taking Starla, Bill and Kylie yell after her, but they call her Carla.
Plot hole: Where did Cross get the blood on his hands? The gloves were clean of blood after he looked at the teeth and removed the gloves, so where did it come from?
Continuity mistake: Nick goes out of his office and to Bristol's desk. Bristol starts standing up. Camera angle changes to Nick then back to Bristol. He starts standing up again. (00:40:40)
Factual error: When the Bronco is underwater at the end of the movie, Claire's hands are tied to the steering wheel. Doug rips the steering wheel off. Anyone who has worked on cars knows you need a puller to get a steering wheel off, you can't just rip it by hand.
Continuity mistake: Hugh Jackman puts a tan vest on twice in the scene when we first meet his wife.
Other mistake: When Joey Lawrence gets his hand cut off by the human, he wakes up to find his arm where his hand used to be wrapped in some kind of black cloth. It's obviously his hand that is wrapped up because the wrap sticks out too far to be only wrapping his wrist. Plus it is also bulky which gives away the hand underneath.
Continuity mistake: In the scene on the roof after the power transfer, Hannah falls through the sky light and Matt yells down to her. You can tell the close-ups on Matt were re-shot because Matt's hair is longer and styled differently in between shots.
Continuity mistake: In the end, all the pictures in the cousin's book are normal, but earlier Leroy tore Xs in each.
Continuity mistake: When they are auditioning for the team, they stamp the fat kid's file "approved" under his photo parallel to the bottom edge. The camera cuts away and back to show the stamp at an angle with part of it on the photo itself. (00:13:40)
Factual error: When Izzy urges Tom to watch through the telescope on the rooftop, he just looks and sees the nebula. From space observations done by myself, I know that the earth rotation is so fast that even for this amount of time, a manual correction must be done to center the view again.
Other mistake: The same shot of two guys looking at a computer while sitting outside on the school campus is used in two different scenes. (00:02:15 - 00:11:35)
Plot hole: If the gasoline in fuel lines and tanks is reaching flash point and exploding, there should not be so many cars just sitting around. Surely all of those vehicles' tanks are not dry.
Continuity mistake: After they ditch Burns in the woods, they plan to go through a small graveyard. As the captain starts briefing the squad we see him taking the cigar out of his mouth. When it cuts the cigar is back in his mouth. (00:21:40)
Deliberate mistake: When Hellboy is attacked by the spider-lady, as the spiders begin to descend on him to steal the sword, you can easily tell that some of the shots of the spiders coming down are repeated 2 or even 3 times, and simply flopped horizontally to appear different.
Continuity mistake: In the scene where Thor hits Hulk with his hammer, he swings it, but in the next shot it shows him with his arm extended as if he hit him with his fist. (01:01:45)
Continuity mistake: In the scene where Dean Cain's character and the girl are chained together with the shackles. Dean leaps through the window and crashes to the floor. The girl then jumps through the window and neither of them is wearing shackles. There was no cut, and no indication they had a key.