Who is connected to my SCOM console

The following command will help to find who is connected to your SCOM console. This works for SCOM 2012.

(Get-SCOMManagementGroup).getconnectedusernames()

For SCOM 2007 you will have to use the ones below. I have not tested the below commands, though.

Get-ManagementGroupConnection | foreach-object {$_.ManagementGroup.getConnectedUserNames()}
Get-ManagementGroupConnection | foreach-object {$_.ManagementGroup.getConnectedUserNames()} | measure-object