There are a number of storage protocol enhancements in vSphere 5.1.
Boot from Software FCoE
vSphere 5.0 introduced a new software Fibre Channel over Ethernet (FCoE) adapter. A software FCoE adapter is software code that performs some of the FCoE processing & can be used with a number of NICs that support partial FCoE offload. The software adapter needs to be activated by the vSphere administrator before it can be used, similar to Software iSCSI.