Plot hole: Had one or more locomotives coupled onto the real runaway's front engine, or even just been pushed by it, anyone aboard the "rescue" engine could have just walked to the unoccupied ones and shut them down - no copters or fireballs required.
Plot hole: In the end, all they have to do is ask the President, when he's conscious (Liev didn't kill him; he just knocked him unconscious), who killed everyone in the control room and nearly killed him. He would know who the traitor is and it's not Salt - when they look back at the facts, they'll see how Salt only killed when she absolutely had to, and how she saved lives and stopped a 3rd world war.
Revealing mistake: When Leo is laying his dead kids on the grass, the little girl keeps moving her eyes and breathing.
Revealing mistake: At the end when Katie enters Hunter's room and throws Kristi against the camera, Katie's reflection in the wardrobe mirror shows her in a different position from when she attacks Kristi, to after she drops out of view.
Visible crew/equipment: Near the end of the boat chase, after the railing and Frank are pulled into the water but prior to the cut to Elise slowing her boat to allow Frank to board, a member of the crew can be seen exiting the cabin of Elise's boat. (00:05:50)
Other mistake: When Lawrence is looking at his wound in the mirror, it has slightly healed. Later, when Sir John visits Lawrence in the asylum, he shows the bite mark he got from the feral child to Lawrence. Since Sir John is also a werewolf, the bite mark should not be there.
Continuity mistake: Saw VII takes place straight after Saw VI. In Saw VI we see Jill put Hoffman in the bear trap and leave. We then see that Hoffman spends around 45 seconds trying to get the trap off before putting in the bars on the window. In this film however, just after Jill closes the door we see the glass break. No delay. (00:08:20)
Continuity mistake: When Ray Winstone takes his pill with whiskey while talking to Mel Gibson, he takes a swig of the drink and knocks the pill back, leaving some alcohol in the glass. When we cut to a wide shot his glass is completely empty.
Continuity mistake: When the police car rolls out of the car wash, both passenger and driver's doors are open. When the shot changes to the deputy holding the rifle, the driver's door is closed. In the next shot both doors are open again.
Continuity mistake: During the close up of Paul writing the word "Mark White" on the lid of the coffin, he is using his right hand. The shot then goes back to Paul, and he is writing with his left hand.
Continuity mistake: When Royce kills the Predator at the end, he slices the head off, and it falls backwards, and the body falls forwards. One of the next shots now shows the head to now be in front of the Predator body.
Factual error: When Ewan McGregor drives to Belmont MA to visit Paul Emmett, he checks the mailbox to see whose mail it's addressed to. It shows the name Paul Emmett, address, Belmont MA 02324, which is the wrong zip code; it is the zipcode for Bridgewater MA, and Belmont MA should be 02478.
Continuity mistake: In the scene when Dalton is climbing the ladder trying to turn on the light in the attic, it shows him stepping onto the same step twice.
Factual error: The Lyceum Theatre, referenced in the film, did not exist in 1828 as it was not built until 1834.
Continuity mistake: When Travis is attacked by Barris at the end of the experiment, he "catches" the knife and his hand is seriously injured, becoming covered in blood. However, when the red light begins to go off and Travis raises his hands to his head, both of them are clean and uninjured. (01:25:25 - 01:26:45)
Continuity mistake: After Kyle dies, Audrey jumps off the diner's roof and starts shooting at the possessed people. She runs out of bullets and gets into the blue van. One of the possessed scratches the top left corner of the windshield. These scratches disappear. (01:09:45)
Continuity mistake: When Aron Ralston falls off the bike he is thrown few yards away of his bike into a bush. However, when he is taking the photo the bike is under his head.
Continuity mistake: When Nina and Leroy are standing halfway up the stairs as he is about to announce that she is the new star ballerina, they both hold a glass of champagne. At first, Nina's glass is almost empty; at the end of the scene however, she is holding a full glass.
Continuity mistake: In the getaway scene where Charlie Wax (John Travolta) reverses into a line of cars to destroy James Reese's SUV, when the SUV explodes the wheels on the SUV change to a stock rim, when it had large custom rims when he parked it.
Factual error: As the three Israeli agents are stepping off a plane in Israel in 1966, one of the cars viewed behind them is a 1978 Olds 98 (with its late 70's square headlights). (00:01:45)
Suggested correction: Not necessarily. Some engines may not have a rear cab access (like Frank/Will's engine had). And even if the rescue engine did have a rear cab access 777's engine only had a side access stair which at the speed it was going is more difficult to climb over from the engine in front of it.
Actually 777's catwalk goes across the front, from side stair to side stair, but someone would have to leap over a rail or a chain to get onto it from the other engine. Why would there be stairs on the right side unless there was a catwalk to get to the door on the left side?