Though not specifically about polyamory, What Do Women Want?: Adventures in the Science of Female Desire"
has been recommended by a few people. Author Daniel Bergner compiled research done by several women sex researchers for the book. Insightful reviews of the book are on Good Reads: http://www.goodreads.com/book/show/1...-do-women-want
I found this New York Times article by the author (from 2009) to be very interesting and thought-provoking: