There are multiple instances of the "S" on Superman's belt buckle being backwards.
During the opening credits, the incubator pod is shown rushing along at tremendous speed just above the ground, but when the wide angle is shown after the credits, there's simply a round crater as if it landed vertically. There should be a long gouge in the Earth behind it and a wall of debris built up in front of it.
At the beginning of the movie, when Lex Luthor drives up to the landing site of the Incubator Pod, a guard in the background appears out of thin air from an animation error.