The rumours are finally confirmed by Microsoft teasing us with news that Vista Service Pack 1 Beta is almost upon us, and even provide a 14 Page PDF Download for those that simply need to know now exactly what the patch will contain:

Windows Vista SP1 is an update to Windows Vista that addresses feedback from our customers. In addition to previously released updates, SP1 will contain changes focused on addressing specific reliability and performance issues, supporting new types of hardware, and adding support for several emerging standards.