For me this isn’t a question of learning the nuts and bolts of a language but rather one of learning to use it fluently and idiomatically.
The first substantive chapter on “essentials” talks mainly about variable declarations and some odds and ends. The most interesting one of these was the behaviour of parseInt which converts a string into an integer. Except if the string starts with a zero, as ISO8601 days and months would, then parseInt assumes it is a number in base 8 (octal)!! I can foresee many long hours trying to debug this problem without this forewarning. This chapter also discusses the importance of coding style conventions.
I found the idea of functions that redefine themselves on first run interesting, it sounds useful and dangerous at the same time.
The code reuse chapter is largely about patterns for achieving inheritance-like behaviour. This introduces a range of patterns which build up to almost exactly replicate class-based inheritance.
There is minimal mention of specific tools or libraries in this regard, although Yahoo’s YUI library is mentioned a few times – Stefanov has worked on this library so this is unsurprising, and not unreasonable.