Service Pack 2 for both Windows Vista and Windows Server 2008 are now available on Microsoft Download. You can download the service pack at for x86, ISO and 64-bit flavors. The updates will pushed through Windows Update at the end of June.
Service Pack 2 for Windows Server 2008 and Windows Vista (SP2) is supports new kinds of hardware and emerging hardware standards and includes all updates delivered since SP1. Among the features it adds are Windows Search 4.0, the Bluetooth 2.1 feature pack, and Blu-ray disc recording support.
SP2 simplifies administration by enabling IT administrators to deploy and support a single service pack for clients and servers. Please see the Windows Server SP2/Windows Vista SP2 page on TechNet/MSDN for additional details and documentation.