You'll want to check out this article and accompanying video -- almost a full half-hour -- from PBS, with Don Hewitt sharing some of his insights regarding 60 Minutes. Thanks to TV Week for sharing this terrific link with us all!
Also recommended is this NY Times appreciation -- they call it "An Appraisal" -- of Hewitt by Mike Hale. It delves intelligently into the historical underpinnings of Hewitt's achievement. Without a doubt he changed television news forever, but that might be giving too little credit to him -- he changed the face and form of TV itself. Quite a legacy, as Hale details for us.