At the ever-swanky Herbst Theatre (401 Van Ness at McAllister), Dave Eggers converses with the subject of his latest book, What is the What: The Autobiography of Valentino Achak Deng, which depicts the recent history of civil war in Sudan, and is based on the true story of Valentino Achak Deng, a survivor of a 1000-mile exodus and one of Sudan's "Lost Boys." In 2003, Eggers and Deng traveled by cargo plane to southern Sudan......