This book is written primarily to an academic audience of professors and graduate students and seems based on a collection of articles written in academic journals. For those looking for a compendium of this research, this book offers a well written summarization. In particular, it does a good job of going through recent ideas of partisanship and what accounts for the changing state of party identification in the U.S. over the past fifty years. Beyond this, however, the book has some important weaknesses. In particular, its big claim to fame is in advancing a new theory of social identification to explain why people cling so tenanciously to their attachments to the Democrat or Republican party. This is fine, except they never really develop their theory in any detal (it is only explained in about 4 pages). So unless the reader is familiar with a lot of social pscyhology their explanation will not have much resonance. More importantly they provide no explicit tests of their theory. I found it ironic that authors who spend so much effort undermining the empirical weaknesses in other research, provide no direct empirical tests to validate their own claims.
What is incredible about this book is its succinct restatement of the body of work these authors have worked on over the past decade and what has come to characterize the state of the field in the macropartisanship in political science. It is an easy read and will definitely become a classic