Speaking of Windows Vista SP1, the final two of three prerequisite updates needed to install Windows Vista SP1 will also be hitting Windows Update. KB937287 which is the servicing stack update and KB938371 which is a multi-component update are both required before installing Windows Vista SP1. KB938371 will not be offered to Windows Vista Enterprise and Windows Vista Ultimate systems until KB935509, the first prerequisite in the series of three, has been installed. Both of the Windows Vista SP1 prerequisites are marked "Important" and will install automatically if you have Window Updates set to the recommended configuration.
Recommended configuration = update automatically, if you don't read Microsoft-speak.