I was playing with Google Finance:
http://www.google.com/finance?q=WEBM and realized that the what used to be a static html page was now a highly interactive application. Of course, I am referencing all of the AJAX functionality that has been added. In many of our current AJAX apps, the focus has been to convert classic applications like email, word processing and spreadsheets into Web 2.0 apps.
The conversion of 'traditional' web pages to interactive apps deserves special attention. This is the science of blending information based on context, degrees of separation and providing the ability to quickly pivot the view. It seems as though there is a point where a web page is no longer really a web page but rather an contextually bound application. The art of blending information, informational views, navigation and functionality will likely be a critical talent of the next gen application developer.