This is the only standard book on the topic so far. Interactive Storytelling is the art to create a complex artificial world, in which a human (player) can unfold an interesting and/or dramatic story by interacting with it. It's the complex level on which interactivity is taking place that makes this field so difficult. Mostly the medium to transport this complex interactions would be some sort of human language, which is horribly complex on its own.

Chris Crawford is one of the few pioneers in the field who is thinking about this for 15 years. In 2004, he squeezed his results in this book (he also founded a company to develop his erasmatron-technology, a tool to build interactive storyworlds).

The book covers the following topics:

-From Story To Interactive Storytelling
-Styles Of Thinking
-Strategies For Interactive Storytelling
-Core Technologies For Interactive Storytelling
-Applications

This gives you a hint what to expect.
The first two chapters will introduce how to think about Interactive Storytelling in the first place: What is different about it? What level of abstraction do you need? How can Geeks and Storytellers work on this together? Also, it tells you what is so "hot" about this topic.
The third chapter lists some basic approaches (of which some won't work for sure, according to the author) and the fourth chapter goes through all the components you'll probably have to implement.
The fifth chapter is a devastating list of work in the field, all but one (Facade) dismissed by Crawford as no real progress.

I think this book is well-written and to the point. Speaking to people who actually try to implement something interesting in this area, it's always an inspiration to me when I pick it up. It is not one of those programming books that lies right beside you while you are working and whenever you have a problem, you look it up. This is due to the fact that this field is totally unexplored (I think everyone is saying this all the time, so I'll soon stop) and no one (or just half a dozen people) have done what you are trying to do. It explains the problem, you get a feeling for what you have to do, and you're basically on your own then.
If you lose inspiration though, pick it up and read a bit.
If you're a writer and for some reason about to conceptualize a storyworld, this book is really helpful for you also. The language is non-techy and you'll understand the medium your work is for.