That's the new book by Joan Roughgarden and the subtitle is Deconstructing Darwinian Selfishness. I'm not sure how true this book is, but if you're looking for a new popular book on evolutionary biology which is engaging, this is the first one in some time.
The book rejects the "Red Queen" hypothesis for why there is sex (e.g., outracing parasites by frequently rolling the genetic dice) and presents a "portfolio diversification" view:
The explanation for why asexual species keep popping up and quickly dying compared with sexual species would seem to be completely explained by thinking of asexual species as genetic versions of get-rich-schemes and of sexual populations as genetic versions of long-term mutual funds, without any need to invoke cost-of-meiosis considerations.
In other words, sex brings a genetic diversity which protects against rapidly changing environmental conditions and thus favors parental genes.
The author also argues against signaling theories of the peacock's tail and against sexual selection more generally (especially on that latter topic I was not convinced but the discussion of sexual dimorphism and why it doesn't always hold is nonetheless interesting). She presents "social selection" as an alternative and if you turn to pp.237-8 you will see an excellent page-and-a-half summary of what the book is about. Male promiscuity, for instance, is viewed as a genetic "tactic of last resort."
Recommended, but with caution. It is a must for anyone who reads about evolutionary biology and by the end of the book I was less skeptical than when I started it.