Factual error: Take a look at Google Earth - the section of the Golden Gate Bridge Magneto breaks off (about a mile - tower to tower plus a section each end) isn't anywhere near long enough to reach Alcatraz from anywhere on the mainland.
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.
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.
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.
Factual error: About 11 minutes into the film, Luthor's yacht is seen in heavy seas in the Arctic. The helo on the helo deck has its rotor blades extended. This would cause immediate damage to them so is never done, even on carriers - the helicopter wouldn't be able to fly properly. (00:11:20)
Factual error: When Liz and Abe's plane crashes, it sinks far too quickly to be realistic. Also, from the sheer amount of force the plane hit the water with, both should easily have died. Obviously done for dramatic effect, but still a mistake.
Factual error: The temperature on earth is increasing more and more throughout the movie. People have been dropping dead left and right, but somehow all plant life is still greener than ever. All the moisture in the ground would be gone by now, so the leaves and grass should be dried up.
Factual error: When, on their second date, Jenny sucks in air and pulls a cab backwards, the driver spins the tires trying to go forward. The smoke rolling off the tires does not get drawn backwards towards the suction.
Factual error: The guy who is invisible is ran down by a car while running after the cop and the scientist. He is shown getting up covered in blood. Everything about him is invisible which includes his blood. It shouldn't have been visible after the accident.
Factual error: General Fury incorrectly uses the DEFCON System. When all of S.H.I.E.L.D's secrets are revealed to the Chitauris, Fury moves to DEFCON 4, which is peacetime with increased intelligence and security. When the threat increases and Chitauri ships are approaching, Fury moves to DEFCON 5, which indicates peacetime. In the DEFCON system, lower numbers indicate higher threats.
Factual error: Throughout the film, most Japanese words are spelled in Katakana. In real-life Japanese, however, Katakana is exclusively used for foreign words adopted into Japanese language, like 'table', 'television' (mostly it is abbreviated to 'telebi') and 'racing car'. But in the film, even indiginous Japanese words such as 'samurai' are spelled in Katakana, not - as they should be - in Hiragana (the syllable system used for native words).
Factual error: When Angier and Cutter are looking for a new workshop they enter a room, with a fully glassed wall on one side. A very modern white radiator is in the room. (00:35:00)
Factual error: Jasper is implied to live somewhere south/southeast of London, however when Theo meets him at the railway station signs can be seen reading "Alresford", the filming location, which is in Hampshire and too far west to be a plausible meeting place.