Continuity mistake: When Steve Martin and Queen Latifa are dancing at the club that his ex wife and her sister are eating at, when the ex wife and sister are talking the ex wife's bangs change from sideswept to centre.
Factual error: In Steve Martin's office, when Steve is showing Eugene Levy the woman he thinks he has a date with, Steve is using an Apple Powerbook on his office desk. It cuts to a shot of the two of them looking at the screen, and then a second shot from across the desk. The Powerbook is still on the desk with the top open, but it is not turned on. When a Powerbook is powered on, the white apple on the top cover glows (even in a well lit room). The apple is not glowing.
Continuity mistake: When Peter goes to his ex-wife's house to pick up the kids, Georgey is seen playing a GameBoy Advance. In one shot you can see the screen of it and it is blank, which means it is turned off. Why would Georgey be playing with a GameBoy when it's turned off?
Continuity mistake: When Mrs. Arness is playing golf the sun is casting a shadow behind her. After she hits the ball she turns 90 degrees and the shadow is still behind her when it should be beside her.
Factual error: When Missi Pyle gets hung on a door handle after her fight this seems impossible. It would've broken off due to her weight.
Revealing mistake: During the fight scene between Charlene and Ashley, Charlene is seated in the chair as Ashley runs over towards her. When Charlene kicks her in the face, a door opens and closes behind her.
Answer: It's called "Way of Life" by Lil' Wayne with Big Tymers and T.Q.