The book "Economic Origins of Dictatorship and Democracy" by Daron Acemoglu at MIT and James Robinson at Harvard is slated to be one of the most important books in the field of political economy for years to come.
Daron incidentally just got the J.B.Clark award this year. The award is given every two years to an American economist under the age of 40 for making a significant contribution to economic thought and knowledge.
Can't wait for the book to come out later this year. You can download the manuscript here and read for yourself how good it really is.