I hadn't heard this particular rumor myself, but Charlize Theron certainly has. It sounds like she would be more than happy to squeeze into Selina Kyle's Cat suit.
"It's news to me," Theron said about the rumor. "But that's kick-ass news. I like that. I think that what has happened to that franchise is amazing, and director Chris Nolan is a genius. So I would be an idiot to not consider that."
Theron is the latest actress to openly express interest in the role. Angelina Jolie, Rhona Mitra, Rachel Weisz, and Megan Fox have all come forward in saying they would like to play the part. Of course, rumors fly over the casting of Catwoman more than any other character. According to an internet rumor Cher was only a whisker away from nabbing the role. So this is probably just more of the same nonsense.
But, for my money, I think Theron is the best candidate for Catwoman I have heard so far.