I have posted a new project on the Xen.org Project page: XenAccess Library.
Project Overview: When running multiple domains (or virtual machines) using the Xen hypervisor, this library will allow a privileged domain to view the runtime state of another domain. This technique is known as virtual machine introspection. The current software focuses on memory access, but also provides proof-of-concept code for disk monitoring.
Primary Contact is Bryan Payne at Georgia Tech.