This is a major shift in web development, and Google and Adaptive Path have been the lead developers with their new applications referenced in the Garrett article. Google suggest is an excellent example of how it functions.
AJAX: A New Approach to Web Applications (Adaptive Path)
AJAX Patterns – Stylish Scripting: The DHTML & CSS Blog
AJAX Patterns Wiki
What Kind of Language is XSLT?
Very Dynamic Web Interfaces – The XMLHttpRequest Object
XMLHttpRequest Usability Guidelines
Principles for a Usability-Oriented Pattern Language
Pattern language is a concept from software engineering as well as architecture that is beginning to be reflected in all design disciplines. William Gibson’s recent novel “Pattern Recognition” (2003) reflects this direction. This article will get you introduced to the concepts if you don’t know about it.