The trailer features some scenes not in the movie: A door is opened for Alex by a porter, during the "Battle of the 80s Has Beens" interview, Alex says that PoP broke up in 1992 and so basically he is a "90s Has Been".
Hugh Grant learned to play piano for the film, and both he and Drew Barrymore learned to sing. However, while you can watch Hugh play on screen, the audio you hear of the piano performance is actually vocal coach Michael Rafter.
When Alex and Sophie are at breakfast, Sophie's cup changes positions several times between shots. Many times, she will lift the cup to take a drink, then in the next shot the cup is back on the table.
When Alex and Sophie are in the piano store, and he is trying to convince her to become his lyricist, as he is playing a piano, the camera reveals the inside of the piano, the piano's hammers are not moving even though music can be heard coming from the instrument.
"Shanti" is a Sanskrit word that means "peace, rest, calmness, tranquility, or bliss." Cora Corman has a strong interest in Eastern cultures and religions, and she uses "shanti shanti" to wish others well. She also uses the phrase in songs such as "Buddha's Delight," a title that is derived from a popular vegetarian dish in Asian cuisines with that same name.