Yesterday Microsoft made public Service Pack 2 RC (Release Candidate) for Windows Vista and Windows Server 2008. There are few things to know, you can only upgrade if you already have genuine SP1 installed, also, this RC is time limited and it will expire June 1. 2010. If you have any earlier release of Service Pack 2 installed, you must uninstall it. Service Pack 2 RC for Vista and Server 2008 can be downloaded here.