One should remember that an web application and a bunch of web-pages serve 2 difference situation. One wouldn't use Ajax for the entire CNN/MSNBC web site. But certain pieces of the sites, could have applications for 'specific' abilities. To the person who said that only certain browsers use 'ajax'. First, can you say 98% (IE 5+,FF,Netscape 7.x,Mozilla) to name a few. Also, when can use hidden-iframes for those version 4 browsers. This covers the majority of a potential user base. The purpose of the web is more than a bunch of pages/documents.