When Lopez pulls over in the tunnel after spotting Ayers, his car blocks the right lane. In subsequent shots, cars are seen in the background cruising through that very same lane, one even merges into it, even though Lopez's car is blocking it just a few yards ahead.
When Lopez leaves the Lamp facility after waiting for Ayers, he gets into his Saab and sees a prostitute walk in front of his car towards some people. She is seen clearly because of the reflection of his car headlights. When the scene changes back to the car, the headlights are not on.
Lopez is seen standing trying to open the drink that was offered by Nathaniel. You then see Lopez leaning against the wall with the can held close to Lopez's body as the camera quickly cuts away between shots.
A utility truck is seen in the tunnel when Lopez and Nathaniel are talking. The utility truck was not there before Lopez stopped his car.
In the movie, Steve takes Nathaniel to listen to Beethoven's Third Symphony. In the DVD bonus material an interview with the real Nathaniel and Steve confirms that this took place, and that it was the Third Symphony. Reminiscing, the real Nathaniel then plays Steve an excerpt on his cello...except that he actually plays the second movement of Beethoven's better known Fifth Symphony - not the Third.
Juilliard dance is not a ballet school. Reference was made to ballerinas and you see them in tutus and make up when he is living in NYC and attending Juilliard. Although they do have ballet classes, it is a contemporary dance focus. They do not do ballets.
In his commentary during the scene when Lopez meets Ayers in the tunnel, director Joe Wright admits that the traffic is all vehicles from the production going around and around (at approx. 17:30). Just after he says that (between 17:35 and 17:59), several vehicles in the background of the shot are indeed visible, though out of focus, making u-turns one after another.
Juilliard is spelled incorrectly as Julliard on his cello case.