1. At the end Tony drives an Audi R-8 e-tron, which is an electric car, and doesn’t sound like the noise heard.
2. Before Tony sends a holiday greeting to the Mandarin his car is pointed one way when he gets in, then the car faces the other direction.
3. When the Iron Patriot Armor is shot at on Air Force One, the bullets ricochet and smash a window. The windows on Air Force One are bulletproof.
4. When Tony is giving his address to the Mandarin through the media the reporter in front of him has a cell phone which changes design between shots.
5. How come the Extremis serum was able to regenerate Ellen Brandt’s arm but not repair the scar on her face? According to the movie, the serum is supposed rewrite the body’s genetic code and constantly repair damaged cells, so her face should have been restored to its original state, just like her missing arm. Even if she had been born with the scar the serum would have healed it, just like it healed all of Aldrich Killian’s physical impairments.
6. One of the Air Force One survivors is shown floating awkwardly on his stomach with his legs in the air. This was due to the floatation device used by the actor, because no unaided human would be able to be so buoyant in a pose like that.
7. When Maya is trying to get Killian to let Tony go, she holds a dose of Extremis to her neck and says “1200 cc’s – A dose half this size, I’m dead.” 1200 cc’s is over 40 ounces. What she’s holding is barely the size of a cell phone.
8. Tony is in the bedroom with Maya Hansen, Happy is seen closing the sliding door. With the door just inches from being fully closed, a quick cut to Tony and Maya kissing, then back to Happy, and the door is almost fully open, with Happy in the process of closing it again just as the plant explodes.
9. When Tony is sending a holiday greeting to The Mandarin, he has sunglasses on. Then in the shot from behind, he doesn’t have any glasses on. Then they reappear in the next shot and then he takes off the sunglasses.
10. When the Mark 42 is “done” assembling for the first time, in Tony’s workshop, a digital model of the suit appears in the lower right corner of the screen. In this render, the suit is complete, but a moment later there is still one piece missing, which hits Tony so hard the entire suit falls apart.
11. When Jarvis wakes Tony up when he is in Tennessee, there is quite a lot of blood on his face. But when he takes off his mask, so before he had any time to wipe it off, the amount of blood decreases significantly.
12. When Tony is in his garage injecting his arm, his chest piece is glowing brightly through his shirt, however, the very next shot when he is wiping his arm with the alcohol pad, his chest piece is suddenly turned off.
13. When Tony and Rhodes leave the Mandarin’s mansion, Tony has blood on his left eye and cheek, which changes to the other eye between shots, then changes again at the boat.