Just got to reach to AJAX enabled Microsoft.com home page which is still in Microsoft Labs being developed and tested !!!
Access the site at,
http://labs.microsoft.com/en/us/
After visiting this, I dont think down the line, there will be any difference between desktop application and web-sites because with AJAX, it's become just like a desktop software.. Just click on the link and without refreshing the page, just content is loaded n refreshed !!
Good going AJAX !!