This blog post has been updated !!!
If you tried our Q1 2009 Beta you have probably noticed that there is a brand new assembly installed in your GAC - Telerik.Web.Design.dll. We decided to separate the design-time code from the web control implementation code. The reasons are many - better separation of concerns, less assembly references for the main assembly (Telerik.Web.UI.dll). We now have the freedom to extend the design time capabilities of RadControls for ASP.NET Ajax without bloating the main control assembly.
Why didn't we make it that way from the beginning? The only reason is that Visual Studio ...