One of the two books I am reading now is PCI Compliance: Understand and Implement Effective PCI Data Security Standard Compliance.  

At about page 50 and nice to see a book that is not obsolete by the time it is print.  Covers the latest rev of the PCI DSS - 1.2.1.  

Seems like a really good guide for anyone dealing with PCI. 

Full review forthcoming.