"How to Improve the Virtual Machine Creation Using a VM Template" -- TechNet Wiki discusses how to use VM Templates in SCVMM 2012 to deploy a server incredibly quickly and easily:
Automation! This is a word that defines one of the best qualities of System Center Virtual Machine Manager 2012 (VMM Server).
In some places it's normal some policies to be used to provide a server in the production environment such as prerequisites, installation, configuration, and others that are necessary, but it takes too much time to be fulfilled. For a Windows basic installation, including updates, usually we need four hours, but with those policies sometimes take days. Compatibility and hardware requirements, applications, configurations and updates are some examples of the bureaucracy that may exist during a server installation. One of the features of the VMM Server to resolve this dilemma is the creation of virtual machines templates, enabling the automated installation and configuration of servers. So we can dramatically reduce the time to release a server and automate all these processes in a simple and uncomplicated method.