You know what's funny? I can't picture Katie saying the same lines that Maggie had in the script. It's like they weren't even meant for Katie to begin with.
The way Maggie delivers the line to Harvey, "Come on, your Gotham's D.A. You're not getting shot at, you're not doing your job right... Well, we could take the rest of the afternoon off."
The way Maggie and Eckhart are walking, and how Maggie is being super-seductive and sexy in her live delivery... it seems so natural with her. There's no way Katie could've pulled that off.
I think Katie has more of a "baby face" where she seems more like a kid, and therefore, she can't scream "sexual" to me. She's just too "cute", whereas Maggie seems older and more mature, and just a flat-out sex kitten. I can't believe that there are people who actually think that Maggie Gyllenhaal isn't attractive. She's freaking gorgeous