Ben Armstrong (aka Virtual PC Guy) posted some great VBScript and PowerShell KVP scripts. These are a great edition to some of my earlier scripts (Adding Host KVP's, Adding Guest KVP's, Modifying KVP’s). Check them out if your looking for more samples.
Sending data from parent to virtual machine via KVP
Enumerating parent KVP data
Taylor Brown Hyper-V Integration Test Lead http://blogs.msdn.com/taylorb