Other mistake: While Fin and the others are on the subway, it keeps cutting to show about 15 people waiting on the platform at Grand Central, and nearly every one of those extras are also seen as passengers aboard the 7 with Fin, in different subway cars.
Other mistake: After the explosion at the top of the Empire State Building, when Fin's soaring through the air he grabs hold of the chainsaw and powers it up to use on the sharks, but in one shot the cutting chain has been removed from the chainsaw's guide bar. Then the cutting chain is back, but it's not moving even though we hear it working.
Other mistake: When Fin is standing atop the fire engine slicing into the overhead shark, the chainsaw's cutting chain has been removed from the guide bar - so it couldn't actually slice, but then the cutting chain is back in place.
Other mistake: The guy eating Subway is at the 96 Street station platform, as seen on the wall behind the bench. The 7 train passes that station and travels on, but later when the train makes the emergency stop, it's at 96 Street.
Other mistake: When Lady Liberty's head rolls down the street behind Ellen, Mora, and Polly, it's a very distinctive street and there's a large white storefront sign 'Aleva' over a green awning that they all pass. Then after they drive off in the truck they're driving down that same street, even from the same direction, with that enormous head still after them. Additionally, that building with the 'Aleva' storefront and its awning has simply vanished the second time around.
