When Abby gets out of the car at the LA hotel, the sentences she mumbles aren't the same words you hear.
When Abby calls Colin the first time and Mike hangs up on him there is a dial tone on Colin's line but the cordless Mike is holding is not disconnected yet. There shouldn't be a dial tone beacause his phone is still connected.
Various cast members refer to the Sacramento station morning show as "a network" or "network program." It appears to be a local TV station.
Mike's show "The Ugly Truth" airs on the local channel 83. Mike asks if Abby is calling from Europe. It's impossible for Europe to receive the channel that airs his show.
When Mike and Abby take off in the hot air balloon, the background shot shows the balloon high in the air (at least above the height of other balloons). However, the next shot of Mike trying to get off shows the balloon nowhere near that far off the ground.
When Abby meets Mike in the hotel lobby, a girl in a blue dress is behind Mike. When Abby enters from the other direction, the same girl in a blue dress is behind her.
When Mike helps Abby talk to Colin on the phone, a green light appears when Colin is on hold. As the scene switches back and forth, the light turns red at one point, then back to green. Colin was on hold the entire time.
Errors in geography
The balloon festival is given to be in or near Sacramento. Sacramento law prohibits hot air balloons from flying around the city due to a fire hazard. It is one of a few cities in the world to have this law. The festival actually takes place in Temecula, over 450 miles to the south of Sacramento.
Incorrectly regarded as goofs
When Mike makes a comment about an "Irish Craig Ferguson," he's making fun of Abby's awful attempt to mimic Craig's Scottish accent; he's not saying Craig Ferguson is Irish.
When Mike and Abby are on camera on the hot-air balloon, it is secured to the basket and balloon lines. When they move around, the basket and lines move with them while the camera remains still.
When Abby is on the "kiss cam" at the baseball game, the Devils are ahead 4-1. The scoreboard doesn't change when the batter hits a run-scoring single.
The warning sign on the back entrance to the news stage is on the inside of the door instead of the outside.