The night before Catch and Sharon's breakfast date, we see that Sharon has a digital clock radio on her bedside table. The next morning Sharon is awakened by an old fashioned alarm clock. Later in the movie, a bedroom scene shows the digital clock radio back again and the old fashioned alarm clock gone.
The bruise on Sharon's chest from the gun shot disappears and reappears several times, before it disappears altogether (which it does far too soon).
When Catch delivers the broccoli to Nora, it jumps from the counter to her hand between shots.
When the waitress brings Catch and Pogue their beers in the bar, she sets down the first one in front of Catch. After the camera angle changes, the beer is in front of Pogue. When the camera angle changes again and the waitress sets down the second beer, the first one is back in front of Catch.
When Catch sits to play trumpet in bar a musician can be seen turning to approach him twice.
When Pogo puts a bag of ice on her hand (after hitting her brother), the ice cubes are clearly plastic.
When Jim Caviezel plays trumpet, he breathes incorrectly and also fingers the valves incorrectly for the notes we hear in the musical cue.
When Catch starts to play the trumpet in the bar, the music sounds as if the trumpet is muted even though there appears to be no mute in the instrument.
The CN Tower and other Toronto landmarks can be seen throughout the movie, when the story is set in Chicago.
When Sharon walks up to the parents' house and meets Kathy, a speed limit sign in the background says "Maximum 40". That would mean 40 kph in a residential area in Canada. In a residential area of Chicago, the sign would read: "Speed Limit 25" for 25 mph.
Although the movie takes place in Chicago, the opening shot clearly shows Toronto's CN Tower in the background.
Tully's coffee cups are shown throughout the movie yet there are no Tully's in Chicago.