The book is very enjoyable. I only recently found out that Chapter 5 has already been available online in a limited, but colorized form as "Casting SPELs in Lisp", http://www.lisperati.com/casting.html

Conrad mentioned that in the next edition/errata he probably will add a (web?) chapter about setting up emacs/slime, but I havent heard any updates about that since the initial announcement.