I turned my back on O'Reilly long ago -- when he turned his back on me and my kind. I don't care about that cafeteria Catholic's motivations and I don't care if Franken and the rest knock him off his perch. Maybe then Fox will exercise a little more discrimination in who they place before the viewing public.
You're making the assumption that Fox News will continue to achieve the same level of success without O'Reilly. I contend that O'Reilly, or a clone of O'Reilly, is the critical ingredient in Fox's viewership levels.
In other words, Fox relies on an O'Reilly-like moderate host, to bring in new viewers and "transitional conservatives".