Continuity mistake: When JB dreams about singing "Master Exploder" in the small bar, he points at one guy in the audience and literally blows his mind. When he starts pointing you can not only see JB's face, but also how his elbow is in a slight angle. In the next shot the camera shows the guy JB is pointing at and his elbow is completely stretched. The views change several times and the angle of his elbow changes after every cut, until the guy's brain is finally blown out.
Continuity mistake: As Dalton stands inside the bank vault staring at the cash, the scene jumps from a wide, distant shot, to medium, to close-in, just outside the cage. Another robber stands just outside and between jumps his gun position shifts from relaxed to raised to relaxed again.
Plot hole: There are six metal bars mounted around the circumference of the water wheel's axle. In the wheel's interior, when Jack frees himself he lands on his feet, begins to run and promptly hits his head on one of those mounted axle bars, then falls out. Moments later, when Jack returns and runs in the wheel, he is shorter (way more than a foot) than all six of the mounted axle bars spinning with the water wheel, which would make that previous shot impossible, however humorous it is. (01:52:40 - 01:53:55)
Plot hole: The snakes escape from the locked box stored in the cargo hold when a small explosive bolt detonates and opens the lid. Post 9/11 all luggage placed in the cargo hold of an airliner would be tested for explosives, and anything larger than half a match head would be detected. The chances of getting an explosive bolt on board - nil. None whatever. You can also think of it this way - if the bad guys could somehow smuggle explosives on board, why bother with such an elaborate and flawed plan as letting snakes loose on the plane? Why not just smuggle a bomb on board? Pan Am 103 - the so-called Lockerbie flight - was brought down with a bomb that fit inside a small cassette player.
Factual error: When performing CPR on Elena, Robert doesn't tilt her head back. As a former firefighter, he would know one of the first steps of CPR is to tilt the victim's head back to clear the airway. His rhythm is also way off.
Continuity mistake: When Bullock is warning Reeves of the coming winter blizzard, she is looking through pictures that depicted her and her friends enjoying the snow. She then turns to the dog and asks "Remember that day? You were not happy". However it's revealed that both characters have the same dog, given to Bullock's boyfriend by Reeves, so when the snow happened in Reeves' time - 2004 - the dog was with him.
Continuity mistake: In a scene towards the end of the movie where Bond and Vesper are lying on the beach, Bond has sand on his back through most of the scene. When they start to kiss, in the distant shot towards the end of the scene, he has no sand on his back at all. (01:57:10)
Revealing mistake: In the disco scene, the DJ is playing music, but the Pioneer decks and the DJ Mixer are not even turned on, as no lights are showing.
Continuity mistake: Right after Queen Latifah hits her head and is having a fantasy, LL Cool J is unbuttoning his shirt. The scene cuts to Queen Latifah and when it cuts back his shirt is buttoned up and his tie is tied properly. It cuts back to Queen Latifah and back to LL Cool J where his shirt is now once again completely unbuttoned. (00:14:00)
Continuity mistake: When everybody is at the rehearsal for Grant and Julia's wedding, when Bernie does a toast to Julia and Grant, watch the level of water in Roz's glass, it changes without her even touching it.