Learning Cython Programming is a short book about Cython – a new programming language, which tries to bridge the gap between Python and C(++). I myself dedicated chapter 9 of NumPy Cookbook to Cython. Cython allows you to call Python libraries from C(++) and the other way around. A couple of examples of this are given in the book. However I think the most important use case for Cython is to speed up Python code. This is demonstrated by a number of recipes as well.
Obviously the author is a skilled developer and he tries to mention his pet open source project as much as possible. He seems to expect his readers to be comfortable with Python, C(++) and *nix like systems (a small group I bet). So this is definitely not a tutorial for beginners. It still beats the online Cython documentation, but the book is too short in my humble opinion. I think that twice as many pages are required to make this a complete tutorial. A couple of pointers for people who are not that familiar with low level systems programming wouldn’t have hurt either.