Today Windows Vista SP1 has made it to Windows Update for the 5 lead languages with the rest to follow over the following weeks. Lots of details at Windows Vista Team Blog : Windows Vista SP1 Released to Windows Update.  Perhaps some of the most important points from the blog entry for me are listed below, but read the blog entry for all details:

1. If in running Windows Update you do not see Windows Vista SP1 listed, there are a number of good reasons for this (Eight in fact, see the whole list)
2. If You have a pre-release version of SP1 and need to uninstall it before installing SP1. This is quite a chore - expect the uninstall to take 30 to 90 mins depending on hardware, then start the whole install process again!!
3. Back in February we announced that we'd be using Windows Update to help make the update as seamless as possible for our users. Windows Update will detect drivers that we know may be problematic when updating to SP1 and will not offer the service pack until an update has been installed. More details about the drives on the blog
4. There is a standalone installer at the Microsoft Download Center here. Windows Update will help ensure a better experience, so if you do choose to visit the Microsoft Download Center make sure that you read these KBs before installing.

I've noticed the benefits on my PC with regard to wireless networks, resume from stand-by, performance of things like file copies and more.

Enjoy the SP1 world.

ttfn

David