Most of the changes required for this support are in the installation process. To benefit from the Vista support, you will have to obtain the new version of the installation media (CD or DVD). As a bonus, the new revision includes all of the latest SAS Enterprise Guide hotfixes (through hotfix 6).
Joshua, as far as I know, there is no firm timeline for this. Some parts of the SAS Foundation have dependencies on a Java runtime, and right now there is not adequate support for the required Java runtime on Windows Server 2008.