Detect the installed SharePoint edition

get-spfarm | select Products

See the article How To: Detect the Installed SKU of SharePoint 2010 on MSDN. It has a list of GUIDs for each SKU: BEED1F75-C398-4447-AEF1-E66E1F0DF91E: SharePoint Foundation 2010 1328E89E-7EC8-4F7E-809E-7E945796E511: Search Server Express 2010 B2C0B444-3914-4ACB-A0B8-7CF50A8F7AA0: SharePoint Server 2010 Standard Trial 3FDFBCC8-B3E4-4482-91FA-122C6432805C: SharePoint Server 2010 Standard 88BED06D-8C6B-4E62-AB01-546D6005FE97: SharePoint Server 2010 Enterprise Trial D5595F62-449B-4061-B0B2-0CBAD410BB51: SharePoint Server 2010 Enterprise BC4C1C97-9013-4033-A0DD-9DC9E6D6C887: Search Server 2010 Trial 08460AA2-A176-442C-BDCA-26928704D80B: Search Server 2010 84902853-59F6-4B20-BC7C-DE4F419FEFAD: Project Server 2010 Trial ED21638F-97FF-4A65-AD9B-6889B93065E2: Project Server 2010 926E4E17-087B-47D1-8BD7-91A394BC6196: Office Web Companions 2010 You can look for these within the registry key HKLM\SOFTWARE\Microsoft\Shared Tools\Web Server Extensions\14.0\WSS\InstalledProducts. You can also use the PowerShell command get-spfarm | select Products to output GUIDs for the installed SKUs.