Revealing mistake: In the scene with the helicopter chasing them down the street, apart from the fact that the rotors should catch on something and hurl the machine into a wall, when it finally hits the wall at the end, the pilot and crew quite clearly become about 4 crash-test dummies. This wouldn't be so bad if it weren't for the fact that they are unpainted and all sit in their seats looking straight ahead with their hands in their laps while they are driven into a wall. You'd think they could have at least posed the arms over their faces or SOMETHING!
Revealing mistake: When Bond holds Carver against the computer so the big drill will kill him, you can easily see that the computer behind them isn't real. As the drill rips into the 'computer' it's all white inside, just like styrofoam. They probably used it as it gets destroyed easily and would make the drill look really powerful as bits of it flew everywhere.