AJAX definitely has the buzz right now, but it might not be the right thing for you. AJAX is limited to
the latest browsers, exposes browser compatibility issues, and requires new skill-sets for many. There
is a good blog entry by Alex Bosworth on AJAX Mistakes which is a good read before you jump full
force into AJAX.
On the other hand you can achieve highly interactive rich web applications that are responsive and
appear really fast. While it is debatable as to whether an AJAX based application is really faster, the
user feels a sense of immediacy because they are given active feedback while data is exchanged in the
background. If you are an early adopter and can handle the browser compatibility issues, and are
willing to learn some more skills, then AJAX is for you. It may be prudent to start off AJAX-ifying a
small portion or component of your application first. We all love technology, but just remember the
purpose of AJAX is to enhance your user's experience and not hinder it.