I believe Rudy doesn't want the job..
I agree, if he wanted it he would have it and he's certainly not going to jump in after this...
no one who has any future political aspirations would take this job. its a thankless position - if everything goes well, no one knows you. if there is a terror attack, you are the scapegoat.
someone like Kerik would have been perfect for this - this would have been the pinnacle of his career, he's not an empty suit paper pusher, he would have just gone in there and kicked some butt and tried to do the best job possible.