When Rosie leaves the car with Greg for college dance, we can listen that the audio of Alex saying "Wanker!" precedes the video.
In the inauguration party of Rosie's hotel, we see Ruby in frame. After 13 seconds, we see Ruby running though the front door which is not possible.
When Rosie is applying to college, she applies to Boston College and yet receives an acceptance letter from Boston University, a totally different college.
Many of the cars throughout the movie were not yet produced in the year it was meant to be.
After Alex moves to Boston for the first time, he communicates with Rosie by text message on a mobile phone with a touch-screen.
Both the Fiat Punto parked near Rosie's house and the Mercedes at the hotel have the same VX02... number plate (possibly identical) despite it being pre 2002.
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