Re: How much change to a character do you consider it a new character.
Different characters, same name, similar history.
Batman: The Animated Series, Batman: The Brave and Bold, The Batman, the Dark Night films and the comics are all distinct interpretations of the same character, but they are different characters.
By contrast, Batman: The Animated Series, The New Batman Adventures, Superman, The New Batman & Superman Adventures, The Justice League, Justice League Unlimited, Static Shock and Batman Beyond all feature versions of Bruce Wayne/Batman that are the same character and take place in the same continuity.