Factual error: Prince Albert was not really wounded in the assassination attempt depicted near the end of the film. Eyewitness accounts differed as to whether he pushed Victoria down to protect her or simply dived for cover himself, but neither of the two bullets fired struck either of them.
Other mistake: In a scene toward the end of the film, there is a shot showing a calendar with the month March 1998. It shows Friday as being the 13th (reference to Philip Morris' birthday), but Saturday appears as the 15th. Did the actual month of March, 1998 not contain the 14th?
Continuity mistake: At the beginning, when Lucy is a guest at Blanche's house for the meatloaf dinner, notice what everyone is wearing, the table, etc. At the end of the movie there is another meatloaf dinner scene at Blanche's house and every single thing is identical to the first meatloaf dinner scene. Everyone is wearing the exact same clothing, eating the exact same food, drinking the exact same beer and wine, etc, and the only difference is Lucy being out of the picture with an empty place setting at the table. (00:10:00 - 01:50:00)
Continuity mistake: When he has the car accident, the blood splat from hitting the bird goes from being an eight inch wide bright red smear of just "blood" that is low and centered directly in front of the driver to a four inch circle with chunks that is high and to the left. It is also totally missing while the car is viewed from above before hitting the water. (01:01:15)
Continuity mistake: While Nia Vardalos is talking to Richard Dreyfus, just after offering him the ice cream cone, the stains on her jacket's left lapel are either there, almost totally disappear, or change shape.
Continuity mistake: Tom receives an e-mail from Summer on day (303). At the beginning of the movie we are told that Tom and Summer met on January 8, so day 303 should be November the 6th, but the e-mail says that it was sent on May 7th, which is day 120.
Continuity mistake: When the tour bus stops at Home Depot, the position of the front wheel changes between shots. Watch the lug nuts and 5 holes around the perimeter of the rim to see how the wheel rotates even though the bus didn't move.
Continuity mistake: When penélope Cruz is sick in bed, a strand of hair appears on her forehead on the last wide angle we see of her.
Continuity mistake: When Walter steps into the cat poo he gets it right under the middle of the shoe. When he then lifts his foot to take a look it's stuck under the front of the shoe with no sign of poo in the middle. (00:17:30)
Continuity mistake: In the scene where Joel, is driving from his house (where he just asked his wife about the filthy pool) to Step's, house (at about 59:14 - 59:17 into the film), Joel's face is not beat up or bruised at all. His face is beat up before and after this scene.
Continuity mistake: During the scene when Ian is taped to the chair, the duct tape across his shoulders changes from shot to shot. Some times it touches the shoulder seams on his shirt, and other times it is several inches away.
Continuity mistake: When Pippa and Herb are having dinner, she hits the table with her fist and wine splatters on his shirt. When he stands up and walks to the bedroom the shirt is spotless.
Plot hole: Mr. Cranston asks Denise to be the accompanist for the school's production of "Chicago". This is an error. In the year 2009, in which the film is set, this would be impossible since the licensing company which has the theatrical rights for "Chicago" restricts the show from being produced (even by amateur groups and schools) anywhere in the greater New York area while there is an open-ended production running on Broadway.
Factual error: When the Lincoln Continental Convertible was rolling backwards down the hill, Nick put his hands on the trunk to try to stop it. A car, especially one weighing 5,000 - 6,000 #, would easily knock over a person and possibly cause serious bodily injury (even death). Nick's attempt to stop the car by holding onto the driver's door handle would also be futile and potentially dangerous. (00:37:47)
Continuity mistake: When Pierce Brosnan is first in the classroom, the writing on the blackboard keeps changing.
Continuity mistake: When the main characters visit Montreal and with their friends they go out to eat at a diner and he creates a "home" out of 4 toothpicks, 3 sugar cubes and a coaster. As the camera goes back and forth in the conversation, watch the "home" on his plate of pancakes. It falls and appears to be scraped and turned in a different direction on his plate by the end of the conversation.
Continuity mistake: After Paul tells Meryl that he was hesitant about adoption during their jogging, Meryl returns home. While jogging, she was wearing very tight grey pants. At the barn, her pants are a lot looser.
Continuity mistake: Mulan tricks her father into taking his medicine, and everyone has a laugh at him. Between shots she is pouring from the teapot first with the right, then the left, and one of the geezers sitting by is cackling with a different posture and hands switched as well. (00:05:10)