Scott announced this morning that the final release of ASP.NET AJAX shipped this morning.
There are already a number of sites out there using the framework. Some of the more recognisable ones are the Live Image Search and Pageflakes and for a NZ example EcoBob although I am sure there are others.
What does shipping mean in this Internet age?
Well it means it is ready for prime time, run it in a production environment for free (whether it is backended by .net or not) and move the support issues onto Microsoft if the framework is not acting the way it should.
I see on the ASP.NET AJAX forums we have more than a quarter of a million users (some working full time for Microsoft answering community questions) generating almost 1.5 million posts on the topic.
Enjoy!