The current Professional-level book you would want to look at is:
http://www.wrox.com/WileyCDA/WroxTit...764579088.html
Although many people think JavaScript hasn't changed forever, looking at a current book like this will help you better prepare for the current ways people use JavaScript, such as Ajax. This book really treats JavaScript as a programming language, which is how you need to think of it if you want to use it for some of the more current applications.
Jim Minatel
Senior Acquisitions Editor
Wiley Technology Publishing
WROX Press
Blog:
http://wroxblog.typepad.com/
Jim's Book of the week:
No book this week - Donate to the Red Cross!