From my recollection there was never anything on the show that contradicted the idea that the various Catwomen were supposed to be different characters. They just appeared as Catwoman, without a reference to them being different characters, from what I recall, but I haven't seen the old Adam West show in years. In any event, that's beside the point. Was the character Halle Berry played Selina Kyle? And isn't Selina Kyle the most recognizable person who has been Catwoman?
No, she wasn't, and a lot of the comic book inspired black characters who have gotten movies over the last 20 years were not from actual comics, which I thought was interesting, and a sign that the comic book companies are not doing enough to develop these characters into motion picture properties.
As for Hancock, I'm not advocating them making Hancock action figures. I didn't like the film. But the point I'm making is that going with established characters might lead to more cross promotion and the making of toys, games, etc. It's harder to do that with original characters, unless you've got a big marketing machine behind you. But even new movie properties like Prince of Persia can reference games and graphic novels, and have something of a fan base because of that instead of manufacturing something whole cloth.