1. A method for providing shared, consolidated storage-related services and high-availability, the method comprising: pairing each of a plurality of discrete block storage virtualization modules to a shared block storage virtualization module, each of the discrete block storage virtualization modules and the shared block storage virtualization module respectively residing on separate application servers, each of the discrete block storage virtualization modules and the shared block storage virtualization modules performing block storage virtualization functions that include presentation of a given virtual disk, the plurality of discrete block storage virtualization modules and the shared block storage virtualization module being distinct from dedicated physical storage resources; maintaining logical volume coherency locally by and among each of the plurality of discrete block storage virtualization modules, and globally by the shared block storage virtualization module; and allocating a set of the block storage virtualization functions to be performed between one of the plurality of discrete block storage virtualization modules and the shared block storage virtualization module according to the pairing, wherein the set of the block storage virtualization functions includes sharing the given virtual disk while maintaining logical volume coherency between a first discrete block storage virtualization module and a second discrete block storage virtualization module of the plurality of discrete block storage virtualization modules, using the shared block storage virtualization module as an intermediary.