AJAX - 04/20/2008
AJAX, or Asyncrynous Javascript and XML is a great new idea in web design. AJAX allows you to refresh page information without refreshing the whole page. A great variety of brand-new websites come with applications that would not be possible if not for AJAX technology. The question remains, however, as to when this technology will mature to the point where it is more widely supported. Currently, AJAX takes advantage of the functions of the most popular browsers. Because of this, less common browsers aren't as likely to support AJAX functionality. This means that non-standard browsers (including Google's webcrawlers) are not able to browse AJAX-dependent websites.
If AJAX were to follow a standard set of rules that non-standard (yet critical) browsers could follow, there wouldn't be a problem. In the meantime, AJAX is a perfectly acceptable way to add functionality at a surface level, as long as the website still functions without Javascript.