For those who have never looked at any lisps, I'd recommend reading http://www.moxleystratton.com/article/clojure/for-non-lisp-programmers before jumping into the book, because the intro chapter has a lot of small examples that you can type in the repl as you go along to get a taste of the language. (this also helps get into the mood to drink the koolaid that the chapter throws at you)
The book then shifts into a more in-depth explanations of different aspects of the languages. The major chapters are: syntax and basic concepts, java interop, the sequences library, functional programming, concurrency, macros, multimethods, and a last chapter about how to go about some common tasks in clojure.
The book provides a pretty nice hands-on experience. As the book progresses, by completing the end-of-chapter exercises, you can gradually write an ant-like build tool. One of the chapters also shows how to write a simple snake game.
So far, I only have a couple of critiques:
1 - imho, getting comfortable with a lisp editor is a big deterrent for Java people, and the book doesn't explain much in terms of what sorts of weirdness to expect in the transition (granted, the book isn't about emacs or vim).
2 - I feel the section about destructuring could be longer and use more real-world code samples, as it seems to be a fairly important concept and, at the same time, fairly novel for the non-lisper.
Overall, though, I find it a nice introduction to the language. The e-book has links any time it references any concept (including the table of contents and the index), making it a pretty decent reference book too.
Has anyone else bought it? What do you think of it?