Hello,
I check telerik.com with these addresses:
1.
http://www.pipeboost.com/getreport.asp?URL=http%3A%2F%2Fwww.telerik.com
2.
http://www.port80software.com/tools/testyoursite.asp?url=http%3A//www.telerik.com
and two site report to me telerik.com has
Uncompressed status and can optimized for at least 200%.
I think it's good if you enable Enabling HTTP Compression on your Windows 2003 Server if your CPU uasge is low or medium.
I found a good article from dotnetjunkies.com that explain Enabling HTTP Compression but remember you also must add js extension to HcFileExtensions attribute becuase you use many javascript files in your site.
Excuse me english isn't my native language.
Best regards
Mostafa Anoosheh