Hi cluster fans,
In Windows Server 2008 R2 Failover Clustering we have incorporated a significant architectural innovation called Cluster Shared Volumes (CSV), which functions as a distributed-access file system optimized for Hyper-V. This means that any node in a cluster can access the shared storage and any node can host VMs, regardless of which node “owns” the storage. This behavior was not included in Windows Server 2008 and this blog will discuss CSV in more detail. For information about configuring and deploying CSV, please check out this guide and be sure to send us your feedback!
Source : Clustering and High Availability