Earlier this week, I told you that Marie Arana, the editor of the Book World section of the Washington Post, was one of several journalists accepting the paper’s buyout offer—a story that was first reported by mediabistro.com’s FishbowlDC late last week. This morning, Publishers Marketplace adds a new detail, with a statement from Arana that she’s already got a new contract with WaPo as a writer rather than a staff editor, and that she’ll be working on a book about Simon Bolivar.