Updated for Hyper-V RTM
Picture it: Sicily, 1914. You've got a bunch of Servers that you need to install and configure Windows Server 2008 and Hyper-V on. You don't feel like messing around with Sysprep. What do you do?
Well, since none of these things existed in 1914, you're probably pretty safe, but that doesn't really help anyone right now, does it?
What you need, is a way to do an unattended installation of Windows and Hyper-V so you don't have to sit there the whole time and type commands when the system is ready for you. Lucky for you, we've already thought of that.
Before you begin, I strongly recommend that you download the Windows AIK for Windows Server 2008 and Windows Vista SP1. The AIK contains tools and documentation specifically for helping administrators just like you to roll-out Windows on a large scale. With the AIK, you'll get a nifty little tool that will help you build unattended installation files (formerly called sysprep.inf, now called unattend.xml). You can download it here.