If you've been an Operations Manager admin for any length of time you've probably had a need to discover security group membership for your various agent computers so if this is you then this is your lucky day. Over on Steve Rachui's manageability blog he posted a sample MP that does this exact thing by deploying a script to every monitored agent that makes an LDAP query to determine the agents AD security group membership and then posting this information back to the RMS.
I'll leave all the details for Steve to explain so if you want more information or want to download his sample Management Pack then visit http://blogs.msdn.com/steverac/archive/2009/01/12/discovering-ad-security-groups-in-opsmgr-2007.aspx.
J.C. Hornbeck | Manageability Knowledge Engineer
OpsMgr 2007: Sample MP to discover AD security group membership Feed: The Operations Manager Support