Recently i've been following James Shore's blog. He's an independent consultant on applying agile methods. It's been interesting to read some of his Essays too. In fact I found his site while googling for Fit and acceptance tests. He just published his new book "The art of Agile Development". It was a no-brainer to order it from Amazon and I just received it!
I'll start to read it and by just looking at the book's index, it seems really interesting. In his page, he introduces the book:
Our goal for this book was to provide a complete how-to guide and starter kit for beginning and intermediate agile practitioners. To keep the book concrete and practical, we focus on XP. If you're new to agile and are looking for a simple, direct, and comprehensive "how to" guide, I think you'll like our book.
You can also listen to a podcast with James about his book on the Agile Toolkit Podcast.