With Windows Server 2008 the newSID tool can no longer be used in combination with imaged deployment of servers. A deployment method that becomes even more important in Server Virtualization and Provisioned Infrastructures. Microsoft has improved the sysprep tooling by using XML config files and introducing the Microsoft Windows Automated Installation Kit (WAIK) to create the unattended answer files. For Windows Vista SP1 and Windows Server 2008, the WAIK version 1.1 can be downloaded here.
For Windows Server 2008 R2 and Windows 7 a different WAIK is to be used, which can be found here.
This post offers step-by-step instructions for the use of the WAIK to setup sysprep.