VMware Virtual Storage Appliance (VSA) v1.0 ? The Facts & The Features | The VMguy:

It is the only scenario where VMware recommends running vCenter on a physical or standalone ESXi hypervisor (To protect you from running into a Catch-22 as vCenter is managing the VSAs 

So VMware (/EMC) add a cool feature to vSphere 5 where vCenter pools DAS on the ESXi hosts into a “vNAS” and presents as clustered NTFS datastore.. but because the controller essentially runs on vCenter, if you lose vCenter you lose your storage.. which is on your storage.. O_o