His book covers all of JS, including more advanced topics like Functions as first-class objects and what closures are, in addition to all of the other bits like how to talk to the Flash plugin, etc. etc. etc.
DOM Scripting—good as an intro to enhancing web pages. Teaches good practices, like unobtrusive JS (keeping JS and HTML separate) and progressive enhancement. It's a pretty quick read. On the negative side, the book uses some simplistic constructs sometimes, and doesn't set a very good example of extracting repeated code into subroutines.