VM is connected to portgroup, so to use HA you should have portgroups with the same name on all ESX servers. But this portgroups can reside on any vSwitch.
VMware vExpert '2009
vSwitch can be different, for example for number of uplink adapters.
VM port group must match (with the same label) or guest will loose network connectivity after a HA restart or after a VMotion.
Other portgroup used by HA heartbeat (vmkernel and service console) must be homogenous (the name could be not important, but the network address must be in same address space).
It is always worth using matching vSwitch names and portGroup names in orde rto standardise your configuration, but vSwitch names is not critical.
doing so, means you can use a script like :http://communities.vmware.com/blogs/virtuallysi/2009/04/02/esx-healthcheck-script-winner
in order to help resolve any HA / DRS and cluster issues you may have.