In one scene, Ryan is upset with his assistant that his next rental car will be a Dodge Stratus. His assistant tells him he is trying for a Chrysler Sebring. In fact, the Stratus and Sebring are essentially the same car. Additionally, the model Sebring pictured (2007-2011), there is no Stratus counterpart as it was discontinued in 2006. It would have made more sense to ask for a Chrysler 300, a more luxurious model than either of them.
When Ryan gets to the airport with the cardboard cutout of his sister & fiancé, you can see their heads sticking out of the top of his suitcase. But when he goes through security, there is no cardboard cutout sticking out.
When Ryan takes a photo of Jim and Julie's cutout outside the Luxor pyramid in Las Vegas, the text and images are digitally removed from a billboard for the live "Criss Angel: BeLIEve" show that is in the shot. However, when Ryan later posts this photo up on the giant map at the rehearsal dinner, the text and images are clearly visible on the billboard.
The scene in which Ryan is in an airport in Detroit is clearly filmed at the McNamara terminal (as can be determined by the iconic fountain and the signs for Continental at one of the B gates). However, it's made very clear in the movie that Ryan only flies on American, and American doesn't have gates at the McNamara terminal (it uses the North terminal).
When the photographer is taking a picture of the wedding party in front of the church, you can briefly see a "Maplewood Methodist Church" sign on the right hand side. Although the scene was filmed in Maplewood, Missouri, the wedding takes place at a Lutheran Church in Waupaca, Wisconsin. All other sign designations identifying the church were changed to fit the location in the film, except this one.
While it is only implied, many of the air shots of the cities visited are not winter shots, but have trees in full leaf. All shots of farmland are have crops. Yet much of the film takes place in the middle of the USA in the winter, with snow on the ground, no leaves on the trees, etc.
At the Hilton Miami, after gatecrashing the Alphatech conference, Ryan, Alex and Natalie take a trip on a yacht (presumably off the Miami coast). However, the yacht is labeled "Three Dog Night, Road Harbour, B.V.I" (for the British Virgin Islands, and with the British spelling for Harbour, not the American one - Harbor), implying this scene was shot about 1100 miles further out in the British Virgin Islands, and not off the Miami coast.
After the rehearsal dinner, Ryan is told to turn up around 5pm for the wedding to start at 5.30pm. In February, sunset is between 5.04pm and 5.42pm for Waupaca, so it would be dark outside, however, when the wedding takes place and into the dinner itself, it is clearly light outside.
During Wichita's layoff, Ryan dismisses a terminated female employee's solemn promise to commit suicide from the tallest local bridge. He becomes visibly distraught upon learning she committed suicide as described. Wichita and surrounding Sedgewick County's tallest bridge is the Arkansas River crossing just 39ft at the peak of summer. The consistently featureless and level terrain plus year round strong winds are crucial for aircraft manufacturers and test pilots.
When Ryan asks how many miles a round-the-world flight would cost, he's told it's 500,000 miles. However, on American a first class round-the-world flight costs 300,000 miles (and even less for lower classes).
Ryan Bingham is consistently shown swiping his credit card or American Airlines frequent flier card horizontally though the slot across the top of the American check-in kiosk to receive his boarding pass. The top slot is only to read passports on international flights. There is a card slot to the bottom right on the American kiosks to check in for flights. You cannot check in by swiping horizontally through the passport slot as Ryan Bingham does throughout the movie.
The movie shows Ryan going in the AA first class line, checking in at a kiosk and then being greeted by a counter agent. They do not put kiosks directly in front of the first class check-in agent. If there is one there (which is rare), it will be off to the side. Finally, the whole point of using the kiosk is to NOT talk to the person at the counter, so even if he had used the machine, he would not be greeted by anyone.
When Ryan checks out of the Hilton, the desk clerk swipes his credit card. At hotels in the Hilton chain, the credit card is swiped at check in and the guest is simply given a bill (usually slipped under the hotel room door) on the last day of their stay. Also, since he's an HHonors member, his credit card information is probably already on file.
In a couple of rental car scenes, Ryan is seen handing his credit card to an attendant, and in one scene asked (as he drove off) for his #1 Club Gold Card. Hertz #1 Club Gold members generally do not have to show a credit card or their #1 Club Gold card - they just walk right to their car, get in, and go. Hertz has their credit card info on file, and when they return the car, they are simply handed their receipt - there is nothing to sign for.
The shuttle bus for the Miami Airport Hilton does not cross any bridges (in this case MacArthur Causeway) going from the airport to the hotel. Hotel only provides complimentary shuttle to/from airport, not nearby destinations
Even very frequent fliers are required to have their membership card swiped by the desk agent at the Admiral's Club. (It's the only way for AA to know how busy a given club is.) The most that would happen if they know a traveler really well is that they wouldn't ask to see their photo ID in addition to your Admiral's Club membership card.
When pictures of Ryan's sister and her fiancé's cardboard cutout are taken at sites of interest, you can see the hand of the person holding the photo. When the pictures are displayed, even Ryan's, the hand of the person holding the cardboard cutout has disappeared. However, the photos were taken using a digital camera. The clone tool and other techniques could have been used to "photoshop" the hand out.
The goof item below may give away important plot points.
Ryan writes a letter of recommendation for Natalie (to be sent to her new employer after she quit CTC) and gives it to his secretary at her desk (to be sent out by mail). The front of the desk has a chrome plated sign which reads "Career Transition Corporation". However, the letter head on the letter received by Natalie's new employer reads "Career Transition Counseling".