I don't know about sysprep but at least you want to run the changesid. Whenever you copy a vm in vmware products you get asked to create/keep the computer identifier. Also the .vmx file in vmware contains the MAC address of the NIC so you could modify this or simply create a new virtual nic so you don't have mac spoofing stuff occurring.
I have not played with HyperV at all to answer unfortunately but hopefully that puts you in the right direction. ~ Upgrade to Next Generation Antispam/Antivirus with Ninja! ~ ~ <http://www.sunbelt-software.com/SunbeltMessagingNinja.cfm> ~
