Factual error: When Howard is running after the bouncy ball he is on the second floor of the Mall of America, however, you see him run through the LEGO store which is located on the lowest floor of the Mall of America, which is impossible if he was on the second floor before.
Continuity mistake: The morning after the party at Steven's, Chip is at Steven's house making eggs for them, watch closely as Chip eats. While they are talking about Heather being a prostitute, Chip repeatedly loses the eggs off his fork, but continues to put the fork in his mouth, and makes a sound like he is actually eating the eggs. He does it about 4 or 5 times during their whole conversation. (00:50:35)
Factual error: When the plane is taking off while the animals are on the runway they duck down hoping it will stop and it becomes airborne shortly before hitting them. In actuality they should have been blown backwards from the jets like ragdolls.
Other mistake: When the general passes the clipboard to the President to sign the nuclear release, the clipboard is actually upside-down. (00:55:55)
Factual error: When the submarine rises in the waters of Norfolk and you see Norfolk in the background, there is one blatant problem. There are NO mountains in Norfolk. Most of Norfolk, Virginia, is below sea level.
Visible crew/equipment: In the scene at the end of the movie when they're in the bar in Mexico, and Archie starts a fight, when you see the dog start to snarl, you can see two hands holding on to the dog's back legs.
Continuity mistake: When Michael Keaton is talking to his wife he picks up Froot Loops, then a second later he picks up Cheerios.
Continuity mistake: Jamie steals a gay magazine at a newsagent. Before he pinches a copy, there are three copies on the shelves. When he pinches it the number of copies on the shelf indeed changes from three into two, but when he leaves the shop, lo and behold, there are three copies on the shelf again. (00:42:15)
Continuity mistake: In the scene where Pauly Shore and Stephen Baldwin's girlfriends arrive right after Baldwin is smacked in the face with the encyclopedia, Baldwin is shown lying on the ground directly above his face, and off to the side. When the camera is off to the side, his braids are in his face, but when they are directly above him, his braids have been brushed away.
Continuity mistake: Towards the end, Danny Aiello fires at James Spader, and we see a brief close-up of the door frame being hit - there are two bullet holes seen in the door - one above and just to the left of the other. Then we cut away, and when we cut back and see James Spader looking around the door frame, there's just one bullet hole.
Revealing mistake: In many scenes, particularly the dance scene in the bar, Michael's wings disappear and/or reappear. If you look closely throughout the movie, his wings are often completely gone.
Continuity mistake: When the former owner of the studio is asking for money, the boom mic is clearly visible throughout the entire scene above the heads of the two actors.
Revealing mistake: When WD-40 is parachuting onto the island at the beginning, he throws a match through his parachute. As the shot changes, you can clearly see the smoke canister that was producing the effect of the parachute being on fire, swinging from beneath the canopy.
Factual error: When The Oneders are recording their song with Uncle Bob, there is an In-N-Out cup sitting by the recording equipment. There are no In-N-Out restaurants in PA.
Continuity mistake: Right after Clooney picks the kids up from pre-school. It was superhero day, so the kids are dressed in homemade costumes. If you watch the little girl, she changes back and forth between superhero and little girl within the blink of an eye.
Continuity mistake: In the scene when Jerry arrives at the top star's house to make sure he's still staying with him, he arrives in an Eagle Vision car, but later leaves in a Pontiac Grand Prix.
Continuity mistake: When Renton goes home with Diane, after they finish having sex, she tells him to get out and leave the room. As Renton sits up, it's very obvious that he's not wearing any protection. Not thirty seconds later, he peels off his condom in the hallway.
Continuity mistake: During the press conference at the U.S. Open where Roy begins to list the companies who are sponsoring him, he says that one of them is "Woody's Smokehouse" when the patch on his jacket says "Wally's Smokehouse".
Visible crew/equipment: Outside the chapel, when Frank backs into the pedestal the statue begins to topple over. In the shot facing up, as the pedestal falls and Frank puts his arms out to catch the statue, the wires used in this stunt are perfectly visible. (01:35:05)
Continuity mistake: In the scene where the Graboid is pulling the truck you can see that there is a gun rack and a gun in it. Right before they are about to hit the rock you can see that the gun falls off of the gun rack. The gun goes on and off the rack between the following shots. (00:30:25)