Reader Brian Donovan contributed the review below of O'Reilly & Associates' ActionScript: The Definitive Guide, which he says is a "must have" for anyone working on Web animation with Flash. Offered under the condition that you please not make your site utterly dependent on Flash, of course;)
What it is, why you'd want itActionscript, the programming language that's been supported in the Flash player and authoring environment since Flash version 4, is exhaustively described in a new title in the Definitive Guide series from O'Reilly. Written by widely-recognized web developer Colin Moock (http://www.moock.org) and edited by Bruce Epstein (author of Director in a Nutshell and Lingo in a Nutshell), the book lives up to the hype.
In the "Applied Actionscript" part of A: tDG, I got the most mileage from the discussion of the different methods of pulling code out of movies and making it more reusable (import from file, #include, shared libraries, and smart clips). Most of that material was already available in separate tech notes at the Macromedia web site (and, to a lesser extent, in the ARG), but it's great to see it brought together in book form.
When I got to the "Actionscript Language Reference," I did a quick page count. It weighed in at 50 pages lighter than the "Actionscript Dictionary" in the ARG, but manages to be more complete and more useful. This could be due to the fact that the pages in A: tDG are covered with text while the "Actionscript Dictionary" pages sport oversized inner margins and whitespace galore. Code is plentiful here, since the entry for practically every Actionscript object or class includes an example script fragment that is generally longer and more useful than the corresponding snippet (when one even exists) in the ARG. Where it's warranted, bug information is included, identifying specific problems with the implementation of the specific Actionscript element in the Flash 5 Player (pinpointing differences in behavior between builds when differences exist) and suggesting workarounds where possible -- the sort of feature that saves coders mountains of frustration of the "it's 4am and I'm tired?why isn't this working?!" variety.
The bottom line
I would have liked to have seen more space devoted to optimization/performance (somehow, code optimization got lumped in with file size considerations in the "The Bandwidth Profiler" section in Chapter 9: "Debugging"), but if it sounds as though I'm nitpicking here, it's because I am. For anyone working with Flash who is interested in taking off the training wheels and developing in "expert mode," this book is a must-have."
You can purchase this book at Fatbrain.