Other mistake: So let me get this straight: Optimus Prime has Energon Swords hidden in both of his arms, with which he can slice through an entire Decepticon in one chop, yet when he is hanging from a few wires, despite having one arm entirely free, he can't cut himself loose?
Transformers: Dark of the Moon (2011)
Ending / spoiler
Directed by: Michael Bay
Starring: Shia LaBeouf, Hugo Weaving, Josh Duhamel, Tyrese Gibson, Leonard Nimoy, Peter Cullen, Rosie Huntington-Whiteley
Sentinel Prime reveals that he worked out a deal to ally with Megatron before leaving Cybertron. Sentinel kills Ironhide and begins to bring Cybertron into Earth with a space bridge. Sam blows up Starscream and destroys the space bridge, destroying Cybertron in the process. Optimus gets his arm torn off but still kills Sentinel and Megatron.
Count3D
More mistakes in Transformers: Dark of the Moon
Jerry Wang: Who wants some chicken dinner now, bitch? Huh? Looks like someone messed with the wrong Wang today!
Trivia: Leonard Nimoy voices Sentinel Prime and towards the end of the movie he has the line "The needs of the many, outweigh the needs of the few". This is the same as his line from Star Trek 2: The Wrath of Khan, where he plays Mr Spock.
Question: During the second movie we see many Autobots, Tex Two Idiot Robotwins and some Motorcyclebots. But now it are only nine Autobots again in the movie. Where did the other Autobots went? Did they got killed or went in hiding?
Answer: No, Sentinel killed both of them in the comics.
Answer: Mudflap and Skids (the two idiot robots I believe you are talking about) were removed from the film due to negative fan reaction. While we don't hear what happened to them in the context of the plot, no reason not to assume they were killed in fighting between the movies. Arcee and Chromia (2 of the motocycles) were killed in the last film.