Continuity mistake: During the scene in which the homeless character portrayed by Steve Buscemi is having a conversation with Longfellow, he is eating a slice of his favourite pizza; French Fries & Oreos. In shot in the scene Buscemi takes a bite out of the slice of pizza, and there is one Oreo on the slice, toward the front of it. Then the shot goes to Longfellow for a moment, and in the next shot of Buscemi, the Oreo is suddenly at the other end of the slice. The Oreo continues moving from the front to the back of the slice throughout the scene.
Deliberate mistake: Am I REALLY supposed to believe that a helicopter is capable of hovering above the top of Mt Everest? [In the DVD specials, the filmmakers say that they're absolutely aware that it's not possible for a helicopter to hover above Mt Everest. They just thought it would be a funny scene if a helicopter pulled the dead guy away from the mountain.]
Continuity mistake: The most flame retardant box of cereal ever! When Deeds saves the woman from the burning building, there is a box of cereal next to the window that is on fire, and only on fire at the top of the box. The scene takes three or four minutes, yet through it all the fire never spreads to the rest of the box or dies out. The top just keeps on burning. Product placement, methinks...
Continuity mistake: In the scene where Deeds is tossing the cats out the window, he throws a black cat with white paws which gets caught by a dog. The dog runs by a guy who suddenly has the cat in his hands without bending over to pick it up. Not only that, but the cat has become grey with black stripes.
Factual error: In the scene when Deeds rescues the woman from the fire, right before him and her jump out the window, all seven cats were rescued, but we can visually see a black cat on the left of the screen on top of the stove. Deeds and the woman jump from the window, leaving the black cat on top of the stove to burn in the fire. All seven cats were obviously not rescued.
Continuity mistake: When Deeds is walking and talking with Chuck and Anderson, Deeds spots Mr. Wetherley slowly walking along the street. Deeds then runs over to him, and offers him a 'lift.' Wetherley is walking past a shop, and there is a bench outside the shop with a little black litter bin beside it. The distance between the bench and the bin changes three/four times between shots.