I'm really, really glad our team did the work to make these publicly available. The Media Center Diagnostic Tool gathers a lot of pertinent information very useful to the team in troubleshooting issues with Windows Media Center. If you ever file a bug report during the beta or are working with someone at Microsoft to determine what's happening it's a good idea to have these tools installed and take a snapshot of your system to share with the person helping you.

Media Center Diagnostic (MCDiag) Tool [x64]
http://download.microsoft.com/download/3/E/1/3E17DF40-EF7A-44DE-8897-685BA68EBD00/MCDiag_x64.msi

Media Center Diagnostic (MCDiag) Tool [x86]
http://download.microsoft.com/download/3/E/1/3E17DF40-EF7A-44DE-8897-685BA68EBD00/MCDiag_x86.msi