Continuity mistake: At the end of the movie, when the Hebrew Hammer is using his Jewish guilt on Santa, Santa is holding his gun. When the shot cuts to behind Santa, he waves his hands in the air and both hands are empty. When the shot cuts back, he's holding the gun again.
Continuity mistake: The position of the cars outside the window changes when Sébastien first meets Nathalie in the restaurant.
Continuity mistake: At one point about halfway through the movie, Jerry Falk sits down in his apartment to translate his thoughts onto his laptop, sort of a mini diary, and the closeup shot of the notebook monitor shows he has typed up over 3 lines worth of text (at 18-point font size setting, no less). Then the next wider shot that includes the laptop screen shows he hasn't finished even the third line; not only that, the text is now in more typical (smaller) font size.
Continuity mistake: When the monster truck rams the back of Adam's car the shot immediately after shows no damage at all to the back of the car. This happens in several scenes throughout the film until the car is eventually destroyed. (00:11:50)
Continuity mistake: Near the end of the film when Ray and Hilda are having a conversation, Ray's white undershirt alternates between being seen and being hidden under his shirt (on his shoulder).
Continuity mistake: In a party scene about 45 minutes into the movie there are numerous shots of the crowd. Over a several minute period one character was shown in at least four shots while smoking a cigarette in a cigarette holder. In all shots the partially smoked cigarette is the exact same length. Either they kept using the same clip or the cigarette was not lit.
Continuity mistake: One scene is captioned as being the end of the summer, and the kids are going back home for school. The next caption, about ten minutes after that scene, tells us that it is six months later, and also Christmas. But Christmas is just three months after the end of the summer, so either the caption is partially wrong, or the few intervening scenes carried us from September to the following June without even seeing the intervening holiday season, and then the caption was meant to jump us by an additional six months.
Continuity mistake: When the family first discover the pram on the road after Brad has been killed, its position on the road changes between the first angle and the second angle from the car. Note the wheels and the yellow line. (00:26:25)
Continuity mistake: Look at the scene where Chanel and her mom are putting on face cream. In the wide shot, Chanel only has cream on her chin, cheeks and forehead. Her mom hasn't applied the cream. In the close-up (when her mom says that they might be moving to Paris), there's cream all over their faces.
Continuity mistake: In the last 30 minutes of the movie, Christina Applegate's character appears to be wearing a black rope necklace tied in the front with the ends draping down the front of her chest. When they arrive at the motel, the necklace changes to a black scarf. In the closeup you can see the sheer material has changed, with the ends of the scarf no longer visible. After she is locked in the bathroom, and escapes, the rope is back, tied in the front. When she gets in a car and is pulled over by the cop, the scarf is back.