Other mistake: When the Penguin is talking on the staircase to his audience of voters, he gives a badge to one young woman. As he lifts it up it is clearly a pin-on design button, however the Penguin leans forward as presses the badge against her blouse as if it were a stick-on design. The badge then stays on the blouse and doesn't fall. (01:00:30)
Continuity mistake: When the joker henchman busts the door and lifts up a flaming stick to blow at a pile of teddys, the angle in which he holds the stick differs through consecutive shots. (00:13:40)
Continuity mistake: When Max leads the Penguin over to the two image consultants, Josh, the male one, reaches back with his right hand for a cigar. In the next shot he's using his left hand. (00:48:45)
Continuity mistake: The yellow bottles of fish food jump from the radio to the fridge, from when Selina arrives home the first time, goes off back to work, then returns back home the second time. (00:22:30 - 00:28:50)
Continuity mistake: When Selina returns home from work a second time she takes milk out of the fridge and pours her cat some. She then starts to drink some, spilling it all down her neck and blouse. When it cuts though her neck and blouse are suddenly cleaned up. (00:29:00)
Continuity mistake: When the Penguin is first talking to Max, about him helping him emerge from the sewers, he spits as he speaks, and black spit covers his chin. The spit disappears when he begins to show Max the toxic waste, then reappears and vanishes again. (00:20:00)
Continuity mistake: Selina dumps her coat, scarf and bag on the sofa seat when she gets home. In another shot the coat and scarf have changed position, and the bag is gone. (00:22:30)
Continuity mistake: As Selina is about to make her cat suit, she grabs a pair of blue handled scissors, yet in the next shot they're pink. (00:31:05)
Continuity mistake: When the camera pans up to show the Schrek headquaters, in the first shot a warm blue light is coming from the windows, and no pillar lights are on. In an overhead shot bright light is on, and emitted. (00:07:00)
Revealing mistake: When Batman makes his first dramatic entrance to fight the clowns in his Batmobile, that clearly isn't snow being churned up by the wheels of his car.
Continuity mistake: After the Penguin bites the male image consultants nose, he has no blood on his chin. In the next shot it is covered in blood. (00:49:45)
Continuity mistake: When Selina puts her soft toys into the sink, she grabs a wooden spoon and begins to stab a pink teddy down into the shredder. But in a closeup she is now pushing a soft toy monkey into the shredder. (00:29:45)
Continuity mistake: When Catwoman smashes a glass display case in Schrek's department store, the position of the items on and around the case change between shots. (00:54:25)
Continuity mistake: When the Penguin is controlling Batman's batmobile, when the batmobile hits a police car, the car flies into a '24 Hours' shop. Between shots the amount of hubcaps and tires hanging on the brick wall around the doorway of the '24 Hours' changes. (01:20:15)
Continuity mistake: When the Penguin pours Catwoman a glass of champagne, the properties of the bubbles and the actual amount of champagne in Catwoman's glass differs. (01:17:40)
Revealing mistake: When the Penguin is controlling Batman's batmobile, when the batmobile hits a police car a wire attached to the police car, pulling it back is visible. (01:20:20)
Continuity mistake: The position of the cards and notices stuck on Seleia's fridge change, from when she gets the milk out of the fridge when she's normal, to when she goes back to the fridge later, after being pushed from the window. (00:22:30 - 00:28:55)
Revealing mistake: When Penguin is controlling Batman's car, cars he is hitting throughout the scene are seen prematurely moving out of the way before he hits them.
Continuity mistake: The location of The Penguin when he falls through the window and into the pool, changes. He moves much further away from the concrete platform. (01:45:50)
Continuity mistake: Catwoman looks at the Penguins enemy list, and it is left with the top page flipped up, but when Catwoman puts the bird in her mouth, the page is back to normal. (01:02:30)
Answer: The film keeps it ambiguous. There are two ways to look at it. Scenario A- She literally died and is brought back to life by the alley-cats somehow, adapting some of their traits. Or... Scenario B- The trauma of falling and sustaining a head-injury, along with her paranoia after Schreck tried to kill her, has driven her mad, and she uses her connection with cats to build a new persona. (Which is supported by the fact that all the things she claims "kills" her with each of her "nine lives" wouldn't actually have killed her. Ex. Her one fall is broken by the kitty-litter truck. Max doesn't hit her in any vital organs when he shoots her. Etc.) Her destroying her apartment is her lashing out at all the things she used to hold dear- her vision of a normal life, etc. It's symbolic of her purging the past and embracing the future. (Plus, oftentimes when people throw fits, they'll smash stuff up).