According to an interview to Star LLC President and CEO Chris Albrecht, live action adaptation of girls with guns action anime series NOIR will be put on hold.

Albrecht further explained that “production challenges on (the series) just became sort of enormous, so we’ve hit the pause button on that,” and put the production team to work on Spartacus TV series, instead.

Noir is a popular series about an assassin named Mireille who receives a message on her computer telling her to come search for the past.
Mireille then heads to Japan and meets a young girl, Kirika, who has an amazing talent for killing. Kirika also has no memory of who she is or how she aquired her special skills. Reluctantly, Mireille teams up with Kirika, not only to find Kirika’s missing past, but also to answer the questions that haunt her own life. They take the name Noir, with no idea of the secrets that lie behind the name “Noir”.

[Source]