What Windows Vista SP1 is - and what it's not

First, a note on service packs. As you are aware, service packs are part of our traditional software lifecycle; they’re something we do for most major products as a commitment to continuous improvement. But, the servicing situation has changed with the advent of Windows Vista, as we no longer rely solely on service packs as the main vehicle used to deploy system fixes and improvements. The Windows Update online service is one new way to deliver many OS improvements. For example, yesterday in advance of SP1 we released via Windows Update two separate improvements to Windows Vista’s reliability and performance. We did this prior to SP1 in lieu of requiring customers to wait for these fixes to be rolled into a single service pack. Beyond this, we improve the Windows Vista experience by continuing to work closely with software partners to ensure application compatibility. We likewise align efforts with partners on the hardware side of the business to broaden the range of devices that work with Windows Vista and to constantly improve device driver quality.

What is SP1? What is it not?
In addition to updates we’ve previously released, SP1 will contain changes focused on addressing specific reliability and performance issues we’ve identified via customer feedback, supporting new types of hardware, and adding support for several emerging standards. SP1 also makes additional improvements to the IT administration experience. We didn’t design SP1 as a vehicle for releasing new features; however, some existing components do gain enhanced functionality in SP1.