At last ASP.NET AJAX v1.0, formerly known as ATLAS, is shipping. This new Web development technology from Microsoft integrates cross-browser client script libraries with the ASP.NET 2.0 development framework - making it easier to develop Web Applications with a rich GUI, and improved user experience.
Complementing ASP.NET AJAX, the ASP.NET AJAX Control Toolkit offers developers a rich variety of client-side controls and extenders through a compilation of code samples and components.
I've been using ATLAS since the early CTP's, and are looking forward to integrate this technology into future Web Applications.
Update: www.aspnethotel.dk now supports ASP.NET AJAX on all web-servers - check out ajax.thinktwice.dk to see it in action!