In one scene, a fan shows a picture of Freddie giving Carly the camera, but iCarly can't change camera angles and there wasn't a camera of that angle in that episode.
Gibby said to his granddad that the Korean war lasted two years. It actually went on for three. Since no peace treaty was signed it could even be argued that it is still ongoing.
To garner the attention of an out of control audience, Sam Puckett points two microphones at each other creating loud feedback. Pointing two microphones at each other would not create any noise whatsoever.