The events of The Killing Joke left former Batgirl Barbara Gordon paralyzed, her time as a crime fighter seemingly over. But she turned her passion for justice and knowledge from her day job as a librarian into a gig helping out Batman, the Justice League, and eventually her own team, the Birds of Prey.
Hacker, researcher, and coordinator of group efforts, she provides research, intelligence, and status updates to superheroes by monitoring internet, phone, and radio traffic, hacking into various government and corporate databases, and having a small army of informants.
Pros: She's a tough lady, and is a rare comic book character who overcomes a disability and lives with it, rather than getting some kind of magical or superscience cure.
Cons: People would want to see her as Batgirl first. And if she's going to be Jim Gordon's daughter, at least 15 years would have to have elapsed from The Dark Knight, since Jim's daughter was just a little girl. Also, movie hackers rarely work as more than comic relief. As a computer nerd myself, that's always bothered me, but in a medium that relies on things like movement, someone sitting in front of a computer isn't very dynamic.
How I'd do it: If for some reason the plot of Batman 3 called for someone to break into a super secret computer or something, I'd just skip the Barbara Gordon part, and have a mysterious hacker using the name Oracle contact Batman (possibly through Lucius Fox, having connected Batman's equipment to Wayne Enterprises) and offer her assistance.
Casting Guesses:Bryce Dallas Howard. Technically she was already portrayed by Dina Meyer on the terrible WB TV series Birds of Prey, but I'd like to see what an actual decent actor could do with the part.
Verdict: Probably won't happen. But I won't say there's no chance, because dropping the Oracle name could count, even though it's little more than an easter egg for fans.
After The Scarecrow, Ra's Al Ghul, The Joker, and Two-Face, who should be Batman's next enemy in the Batman Begins/The Dark Knight series? Well, as of now we know that Tom Hardy will play Bane and Anne Hathaway will play Catwoman.
Check out the master list for all the villains covered. I've pretty much run out by now. Obviously, there are more Batman villains, but not any of significance that I know of. As of February 2009, no one is confirmed as a villain. Not the Johnny Depp Riddler, not Phillip Seymour Hoffman Penguin, nobody.