It can be a little bit frustrating having to wait for a new client or member server to go through its initial polling period to receive its approved updates (once a group policy has been applied). To help speed the process along, I have found the following command to be helpful on our server and client builds (XP, 200x):

wuauclt /detectnow

This command will instruct the machine to check the update server for updates immediately. Additionally, you can apply the /resetauthorization switch to the command to force a new WSUS cookie to be created and update the machine's group membership.

Manipulate Automatic Updates Behavior Using Command-line Options

Event ID 31 — WUA Update Download

It has been a while since I worked with Windows GPO's and I had recently had to refresh my memory while helping a customer deploy a Windows Server Update Services (WSUS).  The commands that I always find myself needing yet always forgetting are listed below. 

These commands are helpful in determining which GPO's are getting applied to a particular server or workstation.  It's one thing to trust what you see modeled in the GPMC, but it's another to see the actual results be implemented on a machine.....these commands help with that.