is gearing up for book release close to the media titan's heart. Winfrey will publish
What I Know for Sure
, a collection of monthly essays she has written for
O, The Oprah Magazine
since it debuted in 2004.
According to a press release, the book will focus on themes of possibility, joy and gratitude. The Mighty O based the title of her column on a conversation with late film critic
The book is slated to hit stores Sept. 2.