VMware's own VSA is certainly an answer - but you're also right about it being targetted to SMB. It's heavily limited - not by choice, but by inherent limitations around how well a VM can replicate itself in order to store further VMs on that very host.
Then you have to deal with that fact that if a version 0.1 piece of software fails, you've lost both mirrors, which is arguably more likely than a single, high quality server failing.
If someone has a feeling that they are a big enough for HA, they should really consider whether they can afford shared storage.