ScottGu在他的博客中说到：

At a high-level, the changes from Beta2 to RC include:

- Inclusion of a built-in VS 2005 Web Application Project template to create new ASP.NET AJAX applications.  This now allows you to pick File->New Project (in addition to the existing template in File->New Web Site) to create new ASP.NET AJAX enabled web applications.

 

- Additional globalization support for AJAX applications, as well as additional script resource handler features to improve substitution logic, compression and caching.  Dynamic invocation of web service proxies from JavaScript is also now supported.

- The assembly name of ASP.NET AJAX changed from Microsoft.Web.Extensions.dll to , and the namespace of the server-side features of ASP.NET AJAX changed from Microsoft.Web to System.Web.  Note that the client JavaScript namespaces did not change (which avoids breaking existing client JavaScript code). 

大致翻译了一下：英文不太好

从高层面来讲，Beta2到RC的变化主要包括：
－可以从一个VS 2005 Web Application Project项目模板来新建ASP.NET AJAX 应用程序。现在允许你从文件菜单中选择新建项目，新网站来新建ASP.NET AJAX Web应用程序。

－增加AJAX应用程序全球化支持，也增加了script resource handler特性来改进逻辑，性能，和缓存。也增加了JavaScript持续动态调动WEB服务。

－ASP.NET AJAX DLL从Microsoft.Web.Extensions.dll 变为Microsoft.Web.Extensions.dll ，服务器端命名空间也从Microsoft.Web变为System.Web。注意客户端JavaScript命名空间并没有变化，应避免破坏现在的JavaScript代码！

他还说到了装配集和命名空间变化的两个原因，这里就不再翻译了。

The team made this last server namespace and assembly change for two reasons:

1) Because ASP.NET AJAX will be a fully-supported part of the core .NET Framework going forward, and so for consistency it makes sense for the final release to live under the "System" namespace - which is where the other core parts of the .NET Framework and ASP.NET live.

2) Because it will help make upgrading to the "Orcas" release of ASP.NET and Visual Studio much easier.  ASP.NET AJAX will be built-in with "Orcas" (so you don't have to download and install it separately), and by making the namespace change it means that your code will not need to change.  You'll be able to optionally keep your applications running using the ASP.NET AJAX 1.0 release just fine if you want (it will run and be supported on top of Orcas) - or you'll be able to change the version string in your web.config file and automatically upgrade to the newer version of ASP.NET AJAX that will be included built-in to ASP.NET "Orcas". 

今天起来后就看到ASP.NET AJAX 1.0 RC发布了，这已经是正式版了，我们已经没有理由不来学习它了，当今WEB开发中，AJAX已经越来越流行，而对于学习和运用ASP.NET的我，学习它肯定是必须的了。而且自从.NET 2.0发布以后，一直关注的就是ASP.NET AJAX，从CTP到Beta，从Beta到RC，以前因为它是BETA可能会有很多变化，只是关注一下，现在真的应该开始学习它了！下面是www.asp.net官方网站说明：

ASP.NET AJAX 1.0 RC Available

ASP.NET AJAX is a free framework for creating client-centric, interactive Web applications that work with major browsers and operating systems. New features include additional globalization support, dynamic invocation of web service proxies, and substitution logic, compression and caching support for the Script Resource handler. The RC release is the final preview of the fully supported version of ASP.NET AJAX, scheduled for release in January.