I bought the book and love it so far; it is not yet complete but the intents of the author are clearly geared toward a rather deep (limited by space though) review of the selected languages;
all this is supported by meaningful projects to get passed the syntax and have a feel of the core decisions that underline every language,
although really essential and important, what bothers me is that, due to some misconceptions about botnets, this kind of effort keeps being presented as a big step towards "less spams" or "less malware" which is wrong on the longer term ...