In the "Chanukah Party" scene, the candles start very short, then grow in the next shot. Other irregularities in the levels of the candles are also noticeable.
When Amanda gets out of the car to run back to the house, the road they just drove down does not have any tire tracks.
When Amanda is drinking her hot chocolate with marshmallows with Graham and the girls, she gets her milk mustache. The milk is small mustache in the middle. In the very next shot, when she hasn't drunk any more, the mustache is large and covers the length of her top lip. Then in the next shot it is small again.
Near the start, when Ethan heads upstairs to talk to Amanda, she throws a trainer/sneaker at him. It disappears from where it lands in the next few shots, then reappears when Amanda throws the second one. Then when Ethan is next seen and the camera tracks across the room, both trainers/sneakers have disappeared.
The position of Amanda's bra strap changes shot to shot while she's talking with Graham in bed.
When Arthur asks Iris where she is from in England, she answers: Surrey; Arthur then says that Carey Grant came from Surrey which Iris confirms. This is wrong as Cary Grant came from and was born in Bristol, England.
(at around 32 mins) While Amanda is lying in bed in England, she sees an advert for the movie "Deception" out on Christmas Day. Movies don't show on December 25 in the UK; it would come out on 26th December and would say "Boxing Day".
When Amanda is choosing the destination country for her trip, there is no actual Polish flag next to the name Poland in the menu, but a pattern that looks somewhat like an Austrian flag flipped 90 degrees.
When Iris is on the plane to L.A., she is replying to a message from Jasper on her blackberry. When she has sent it, there is a quick shot of the 'message sent' confirmation, and the date shown is "WED, DEC. 18". However, the film is set for Christmas 2006, and the most recent time that December 18 fell on a Wednesday was 2002.
When Amanda is lying in bed in England and sees her advert on the television, it is clear she is watching Little Britain (2003) before it comes on. 'Little Britain' is broadcast on the BBC in England, which gets its money from TV licensing and does not show adverts. (Although it may however have been shown on the cable channels Dave or G.O.L.D. which are both commercial networks which do have adverts.)
When Amanda is looking through a list of countries to visit on the internet, the icon next to South Africa is a picture of the old South African flag, which was replaced in 1994. However, it may just be that she is looking at a website that's not up-to-date.
When the limo is returning Amanda to the the cottage before New Year, the shot towards the driver shows the scenery moving by, yet both the tachometer and the speedometer readings are zero. The car is either not running, or the gauges do not work.
When Iris and Miles are in the video store, Miles selects Gone with the Wind (1939), Jaws (1975), and The Graduate (1967) all from the same section. Jaws seems out of place in what is labeled Classic Drama.
When Amanda is singing and dancing in the cottage, she is holding a glass of wine, then it's gone from her hand but she never put it down.
When Amanda is searching for her holiday, on the net appears a window with the countries' flags. The old South African flag is used instead of the current, Peru's flag is used as Poland's and Union Jack is used as England's flag.
The green band before the "Deception" trailer reads. "The following trailer was deemed suitable for all audiences by the Society of American Filmmakers" At the time of the film's release, the green band for trailers would state, "The following preview has been approved for all audiences by the Motion Picture Association of America, Inc."
In the beginning, when Miles is producing a song for a movie, he hits all the wrong keys even though the computer screen shows the correct notes.
When Amanda pours herself a glass of white wine, the "glugging" sound effect begins well before air starts entering the bottle.
When Graham is wearing his glasses the kitchen after the first night with Amanda, a camera light is reflected in the close-up of his face.
When Iris arrives in L.A. and is taking a taxi to Amanda's house, the cab drives along with the ocean to its right and turns left onto Sunset Blvd - this means that it is driving south. To get to Sunset Blvd from LAX airport, however, one would need to drive north.
Although the English scenes are set in Surrey, the cottage is typically Cotswold, as is the "restaurant" used in lunch date scene, which is ironic as "The Cotswolds" was first rejected by Amanda.
When the camera pans away and shows the limo taking Amanda through town on her way to find Iris's cottage, the cars are driving (and parked in town) on the right side, not the left side as it shows later when Amanda drives to town and almost hits someone because she gets on the wrong side.
When Amanda is first taken to the cottage she has to walk as the limo can't get up the path, later when she wants to go back to the cottage she has to walk as the limo can't make it up the path, however when she is going home after the holiday the (exact same) limo is waiting outside the gate for her at the top of the lane it apparently can't get up.
When Amanda first meets Graham, at approximately 1:10 AM, she says that she arrived around six hours earlier. That would be 7:00 PM. It would have been completely dark outside at that time of year in that location. Yet Amanda was seen arriving at the cottage while it is still daylight.
When Iris is driving Arthur back to his house, he asks where she is from. She says Surrey, to which Arthur says Cary Grant was from Surrey as well, to which Iris agrees. Grant was from Bristol, which is not in Surrey.
Graham told Amanda that he is a book editor. She asks what kind of editor he is; does he give notes? Graham says "The better the writer, the less notes I give." As a literary editor, Graham would know that 'less' is grammatically incorrect; he should have said 'fewer'.
Iris briefly considers ending it all by breathing in gas fumes from her cooker, but the UK changed to natural gas decades ago. The previous Coal Gas would put a person to sleep with a couple of breaths and kill them in minutes. Natural gas is not toxic and could only kill someone by displacing all the air in a room, which is unlikely, as it is lighter than air.
When Graham and Amanda are laying in the tent with the girls, one of the girls says something about never having grown-up visitors that are girls. It's likely that their Aunt Iris would visit on a regular basis.