Determine the edition of SharePoint Server 2007

To determine which edition of SharePoint Server 2007 is installed for the purposes of inventory, the following registry key can be interrogated.  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office Server\12.0\OfficeServerPremium If the value is 0 then the edition is Standard.  If the value is 1 the edition is Enterprise. The screenshot below helps to illustrate this.