It isn't clear what role Marion Cotillard would play, if she is coming aboard. There has been speculation that Talia al Ghul will appear in The Dark Knight Rises, so it's possible Marion Cotillard could be up for that role.
The Dark Knight Rises starts shooting this spring.
The Dark Knight Rises was released July 20th, 2012 and stars Tom Hardy, Christian Bale, Anne Hathaway, Liam Neeson, Joseph Gordon-Levitt, Gary Oldman, Marion Cotillard, Morgan Freeman. The film is directed by Christopher Nolan.