Find out who is connected to your SCOM 2007 management group

As we all know, we can see how many concurrent SDK connections have been established on the RMS by looking at the Client Connections counter in OpsMgr SDK Service:

To find out who are actually connected, you can use the SDK:

[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.EnterpriseManagement.OperationsManager.Common") 
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.EnterpriseManagement.OperationsManager")
$RootMS = "SCOM01"
$MGConnSetting = New-Object Microsoft.EnterpriseManagement.ManagementGroupConnectionSettings($RootMS)
$ManagementGroup = New-Object Microsoft.EnterpriseManagement.ManagementGroup($MGConnSetting)
$ManagementGroup.GetConnectedUserNames()