Cisco Nexus 1000v
The Cisco Nexus 1000v switch is a new virtual appliance that replaces the built-in vSwitch that comes with the VMware ESXi hypervisor. It brings all of the benefits of having a Cisco operating system and features into the virtualized environment. The Nexus 1000v is HA aware and extends all it's switchports to all vHosts. It's important to stay on top of firmware and new OS releases as each release is a huge step forward when it comes to these new virtual things.