Character mistake: The Christmas card to the Prime Minister from Natalie misspells Christmas - the "r" is omitted.
Factual error: When Billy Mack hears he is No. 1, the DJ, (Radio 1's Wes, who does the chart in reality) says the two singles which could be No. 1, then announces Billy is and plays it, without playing the no. 2 song first. The chart is done as an uninterrupted countdown, so even if it's known what no. 1 will be, they'll still play the "losing" song before it.
Revealing mistake: This is really a reverse mistake resulting in NON-visible crew. When the U.S. President's black limo arrives and stops so that the camera is facing the car's left rear side, you can see that the car has been smeared - unevenly - with some sort of gel to prevent us from seeing the reflection of the lights, crew, and the set opposite Downing Street.
Chosen answer: Irrelevant when it comes to soundtracks, Girls Aloud released a version of Jump to coincide with the movie's release and the video for the song featured scenes from the movie, hence its inclusion.
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