Digital Oprah to Publish Book of Magazine Columns By Chris O'Shea|March 12, 2014 Share By Chris O'Shea|March 12, 2014 Share Each issue of O, The Oprah Magazine closes with the “What I Know for Sure” column penned by Oprah. Readers love them, so Oprah is taking those columns and stuffing them inside a new book by the same name. What I Know for Sure will be published in September by Macmillan’s new non-fiction imprint, Flatiron Books. The columns inside will be updated and organized around very Oprah-sounding themes like joy, gratitude, awe and possibility. The new book — the media maven’s fifth — will be further proof that Oprah knows more than you. Or at the very least, is good at faking it. Adweek Adweek