* this is a rated review of a book, not a language! *
Very dense, intensive & demanding (no easy fly-by), but on the other hand also very competent & packed with reasonably filtered material. Contains pretty much everything you need to start writing Clojure *language-wise* & even much more. Why language-wise? Because there'a almost nothing about the tooling - IDEs & other enhancements that could appear helpful in starting adventures in Clojure.
If you've seen the criticism for Edition One, I've got good news for you - at least in my opinion they do not apply to Edition Two.
Book is relatively up-to-date. AFAIR it covers 1.6 while the latest version (at the moment I'm writing this review) is 1.8.
What I really liked, NO, even loved about this book is that it doesn't follow the usual boring route of presenting just the basic syntax elements & 101 code samples - author isn't afraid of digging into actual reationale behind some more advanced constructs, some macro / closure considerations are really thorough, complex & require full focus to follow. Thumbs UP!
It's not the easiest lecture, but if you're already an experienced functional programmer who wants to learn Clojure - this book may be exactly for you! Recommended.