TechNet shows two parameters for the Automatic Updates Client /DetectNow and /ReportNow. Someone did a bit of digging and posted the following parameters in a comment in the community section of this page on the TechNet site. I tested several and they actually work even on Windows 7. Some of these parameters launched UI elements that would not be of any real value when working from the command line…This may explain the reason they are undocumented.
A Gem Amongst the Rubble
There is one very useful parameter in this list – /UpdateNow. It actually causes immediate installation of updates. This would make a great agent task in a community MP!
Full List of Parameters
From a dump of the .exe W2k3 R2 version you can extract the following parameters:
Most of these options don’t give any noticeable response, but that may be because of the state of the service.