ASP.NET AJAX Beta 2 was released on November 6 and includes several improvements over the first Beta including the UpdateProgress control which moved from the CTP to the ASP.NET AJAX Extensions (core), and improvements to ScriptManager for better loading of scripts and localization.   More information is available on the ASP.NET AJAX site or you can use the links below to download:

ASP.NET 2.0 AJAX Extensions Beta 2

ASP.NET AJAX Futures November CTP

ASP.NET AJAX Samples

ASP.NET AJAX Control Toolkit

Known Issues at Release: 

• The ASP.NET AJAX Control Toolkit uses the Microsoft.Web.Extensions.Design.dll assembly for some controls but the assembly isn't installed if Visual Studio isn't detected during installation.   To fix this, you can manually copy Microsoft.Web.Extensions.Design.dll into the local \bin directory of your application.
• If you're using the Microsoft AJAX Library with ASP.NET AJAX applications, the ScriptManager expects to find scripts under a different directory path than is created by default by extracting the ZIP archive.   To work around this problem, create a new directory tree: %Program Files%\Microsoft ASP.NET\ASP.NET 2.0 AJAX Extensions\v1.0.61025\MicrosoftAJAXLibrary\Microsoft.Web.Extensions\1.0.61025\ and copy the installed scripts under this path.

Also, check Matt Gibbs' blog for additional known issues with Beta 2.  

-Rich