Since we don't have any Groups here, I thought it might be useful to post what little I've learned about the tools available for Win8 Activation/Validation scenarios.
1) MGADIag will run - but is almost irrelevant, as much of the information it checks has moved
2) The tool which is replacing it is built-in to the OS - as LicensingDiag.exe.
It must be run under an Elevated Command Prompt (or Powershell) and requires two parameters
-log <CAB filename>
Note that it will run with only the -report parameter, and produce the output file - but that it will then ingracfully crash. I hear that there are battles within MS to get it to behave better, or to default on any unentered parameters
3) The output is vastly different to that from MGADiag - and from what I've seen so far, is a lot less informative....
Here's the output from my current VM
Note the lack of a File MisMatch section particularly. I've had problems getting anything to come up in the TamperedItems section of the report without physically changing files - permissions seem to make little difference, and many of the files that I expected to be tracked don't appear to be, and the error messages that appear in the MGADiag File Mismatch section don't appear in the TamperedItems list when a file is detected as tampered - so you have no idea where to start looking for a problem.
<ProductName>Windows 8 Consumer Preview</ProductName>
<TimeZone>GMT Standard Time(GMT)</TimeZone>
<ActiveSkuDescription>Windows(R) Operating System, RETAIL channel</ActiveSkuDescription>
Obviously, there's no Office section, since the OGA program went its own way at the launch of O2010.
As far as validation goes, it appears to be 'normal' - but the normal manual validation methods don't operate.
Going to www.microsoft.com/genuine/validate I get an Unsupported OS error.
Attempting to download WinXP Mode, I get directed to a mess
Downloading a WGA-required item from the Download Center, validation appears to work as normal.
HTH - I'll add more when I know more.