For the very few of you running Windows Vista (please, run Windows 7 RC1, its way better), or the larger crowd of server 2008 users, Microsoft has released service pack 2. What happened to server 2008 SP1? Well it was built into the RTM release, so it was never a separate download. Kind of weird having a service pack built-in to the first release of an OS, but that’s Microsoft for ya.
Since Vista and server 2008 share the same code base, they use the same service pack installer. You can find all the downloads here.