Corrected entry: In the scene where the pachyderm animals of Mordor are introduced in the battle, there's a shot that pans the front of the line of them. One animal has wood connecting its larger tusks, complete with barbs jutting out from the wood. As the orcs flee to regroup behind the animals, several run through the contraption unharmed.
Corrected entry: When everyone is leaving to go to the battle at the black gate, Minas Tirith is shown as a battle-scarred city, with burned, gaping holes in the walls and towers from the damaging barrage of catapult-thrown boulders. The next time we're shown the city, after the battle, it's all fixed up.