The Battle for Compassion: Ethics in an Apathetic Universe is a new book by first-time author Jonathan Leighton. He argues for 'negative utilitarianism plus', which means negative utilitarianism that nevertheless values existence. Chapter 13, 'Where We're Headed', discusses the Singularity at some length and mentions Yudkowsky several times. (Click 'Look Inside' on Amazon and search for 'Singularity' or 'Yudkowsky'.)
The book is written for a popular audience and does not reflect my views.