Contributed By: DrC
When SUS installs an update, it does it using pre-defined switches that can’t (or shouldn’t) be modified. All updates install through SUS (Automatic Updates) in "silent" mode in that they don’t require user input, although you may see a "file copy" dialog while some updates install…but that’s pretty rare. As far as reboots, if the content provider (whoever gave the update to the Windows Update team) specifies that it requires a reboot, then the Automatic Update client will prompt for a reboot – there’s no way out of that.

Two commonly requested features for future versions of SUS have been to provide for completely silent installs (no user notification at all) and for the ability to suppress reboots. These requests have been passed to the SUS design team in Microsoft. It is unclear at the moment what will happen with providing silent installation capabilities, but it seems unlikely that the option to allow users to suppress reboots will be provided since installing an update that requires a reboot and NOT rebooting may leave the machine in an unstable state.

Additionally, updates are intended to fix something, and until the reboot occurs the machine isn’t "fixed" even though the patch has been installed. This is mostly due to the fact that when an update requires a reboot, it is usually to replace system files that are currently in use, and until the reboot occurs the system continues using the older un-patched version of those binaries.