Had Jobs been threatened with jail time, I wonder how much public backlash there would have been. As blind as we may want justice to be, nobody can overlook the fact that the man was responsible for some really nice gadgets. On top of that, the story is hard to get across to the general public: some stock back-dating and ebook price-fixing with no clear sympathetic victim. In light of that, I can see why the DoJ didn't charge him. They would have risked public opinion demonizing the prosecution and favoring Jobs no matter how guilty he was.