I was disappointed to see that the previous reviewer thought so little of this book. Personally, I thought it was excellent. As a systems analyst, I need to employ use cases as a way for users to understand how they would use the system - in 'everyday' language. I thought this is precisely the reason why the book was written. Rarely can I get users interested in state diagrams, event/action analysis etc. Users that have this ability don't need use cases:-)
Also, I felt Cockburn clearly explained where use cases sit with regard to other requirement types. If you want a good book that shows you how to write behavioral requirements in 'user-speak', this is the one!
I think there are many good books, which show how to take use cases down to a more formal representation for development purposes. "Applying UML and Patterns" by Craig Larman , Second edition is one of them. In it, he describes the refinement of a use case into system contracts with pre-post conditions, static model etc. Another great book!