The ActionScript ecosystem is vast. No single book can cover it all. Noteworthy topics that are not covered extensively in this book include:
The Flex framework
Flex Data Services
The Flash authoring tool's built-in components
Flash Media Server
ActionScript's regular expression support
For information on these topics, see Adobe's documentation and O'Reilly's Adobe Developer Library, at http://www.oreilly.com/store/series/adl.csp.