Zatanna may indeed be coming to the big screen, though not as a solo character. She's one of the supernatural characters in the so-called "Justice League Dark" project that Guillermo Del Toro is in talks to develop
Gotham Central wrote:
Catwoman...this could work, but only AFTER another Batman reboot.
I think just the opposite -- we need an Anne Hathaway Catwoman spinoff.
As for other DC female characters, I think Big Barda has a lot of potential, but she'd kind of have to be part of the whole Fourth World thing. Power Girl might work, if you could come up with a good origin story that wouldn't drag in all the continuity baggage. And though I haven't read anything involving her, I've heard a number of things about a character called Manhunter, a lawyer who takes on a superhero persona. I can see how that could have TV-series potential -- what network exec doesn't love lawyer shows? Not sure about movies, though.