Continuity mistake: When The Ark escapes Cybertron it is hit by a missile tearing off a massive chunk out of one of its wings. Yet when it crashes on the moon, both wings are fully intact.
Continuity mistake: During the final fight between Optimus and Sentinel, a long curved copper pipe going from Sentinel Prime's chest to his right arm disappears and reappears between shots. And it isn't torn of in the fight between only the Prime's, I cannot say if Megatron doesn't remove it later on.
Other mistake: When Sam and the others are in the building, and then sliding down the side of it, the angle at which the building is compared to the ground seems to change many times. The angle, rather than simply increasing gradually, goes from very large (when we first see the Decepticons firing at its base) to very small (when we focus back on the team inside the building and the chairs are only just starting to roll across the room, indication that the building is barely slanted) and then back and forth between large and small depending on the angle of the shot when they are sliding down the side (and this is not just an impression due to the angle of the camera). When they then break through a window and come back into the building, the angle of the slant is again too small. (01:53:45 - 01:56:30)
Continuity mistake: During the freeway chase scene, Bumblebee widens his tires considerably for better braking abilities. In the next shot, the rest of him/the car is instantly semi-transformed.
Continuity mistake: When Carly shows Sam the stuffed bunny, her hair is curly. Then when she jumps on the bed, her hair is straight.
Continuity mistake: Sideswipe's rims keep changing throughout the movie. At some point he has rims which have a pretty big distance between the edge and the actual spokes and at other points he has rims which have the spokes on the edge of the wheels all together.
Revealing mistake: When Optimus has his 'rage' on Wacker Drive, you can see that cars that are being flipped not entirely by volition, since some of them (most notably the red BMW before he cuts a Decepticon clean in half) aren't even touched by Optimus or any Decepticons. (02:15:15)
Suggested correction: Actually if you look real closely, then you will see a shot, which resembles that of Bumblebee's.
Audio problem: In the scene where Dylan is explaining the Decepticon's plan to Carly, there is a shot of Sentinel Prime moving the control pillar into the tower. During this shot, if you look to the left, you can see that Dylan's mouth is not moving when he is supposed to be talking.
Continuity mistake: After Optimus saves the day by shooting the Decepticon hovercraft, we get a small speech. When he says: ''For today, in the name of freedom'', his gun disappears. We never hear him throw it away, or see it lying around when Bumblebee transforms. (01:39:50)
Revealing mistake: In the Chicago battle scene when the two small autobots bring down the large decepticon ship, just after the ship runs into the building (Key Tower, Tribune Tower, or Pittsfield Building), the CGI detail is unrendered and the top of the building is only drawn in plain polygon.
Continuity mistake: When Sam leaves for his job interviews he sees his parents and drops his jacket, he then walks back into the apartment and comes back out with his jacket in his hands.
Continuity mistake: When Optimus arrives in the street where he battles Shockwave, he passes the firetruck (behind which Sideswipe takes cover) twice.
Visible crew/equipment: In the shot of Optimus driving along with the Driller, part of a camera mount can be seen in the reflection of Optimus' chrome grille. It's definitely not something next to the road, since it's moving at the same speed. (00:18:25)
Continuity mistake: When Sam first meets Dylan Gould at his showroom/office, there is a close up of Dylan using an iPad which he hands to his assistant. His assistant then folds her arms, covering the Apple logo. In the next shot it has been repositioned to show the logo.
Plot hole: In the scene where Sam and Carly are attempting to communicate to the military through the UAV drone, Sam tells them all about the Decepticons' plan to bring Cybertron into our atmosphere. But Sam was never there when Dylan explained the plan to Carly, and there was no time for Carly to have told him.
Other mistake: In the scene where Laserbeak picks up Sam and drops him off the building, Sam smashes through a glass wall with a handrail. Earlier on, he climbs over this handrail. No way would he have the momentum to smash a metal bar.
Factual error: Cybertron is placed between Earth and the Sun, as you can see in the shots from outer space. But it doesn't see to block the sunlight, despite being notably bigger than the Earth. It may be a framework but it's very dense with multiple layers.
Revealing mistake: When Optimus uses the Shockwave cannon to bring down the cupola with the control pillar in it, the cupola starts falling before the bullet hits the building.
Continuity mistake: When Ironhide crashes into the remaining dreads and transforms, one of the dreads is shown falling into some kind of wooden box covered with glass breaking it apart. In the next shot the Decepticon stands up and the debris is not visible.
Revealing mistake: During Optimus Prime's rage the same red BMW gets flipped three times.
