Indeed, and that's one of the things I find attractive about it, especially since I believe Lisp is the One True Way and much of the parsing effort that VPRI worked on is irrelevant to me (but not things like the idea of parsing illustrations in RFCs and generating a TCP/IP stack!).
As for the book, right now the work on the project by the author is supported by direct patronage or buying his books. And there's much more in the book than just "leaning Shen". Here's the web page for it: http://www.shenlanguage.org/learn-shen/TBoS/
Which includes the preface, table of contents, and conceptual dependency table, i.e. what previous chapters you need to have mastered to understand each chapter.
From the chapter titles and subtitles, here's stuff that goes substantially beyond "learning Shen":
Higher Order Functions (e.g. partial application and currying)
Non-determinism (non-deterministic algorithms)
Shen-YACC (sigh, needed for e.g. pattern matching)
Lambda Calculus
Writing Good Programs
Sequent Calculus
The SECD Machine
Shen Prolog (12 pages on Prolog per se)
The Compilation of the Sequent Calculus
And there's a
lot of material on types (one of the features of Qi/Shen). So you get a whole lot of CS exposition in the context of Shen.