In this particular case, vCenter was physical. However, to answer your question, VMware HA will continue to work—once it has been configured—even when vCenter Server is unavailable. This is one of the reasons why running vCenter Server as a VM might offer benefits, in that VMware HA can help provide availability for vCenter Server itself.

Hope this helps!

It’s extremely cool, and extremely valuable to the business. You’ll have to make your own decision as to whether the cost of VI3 Enterprise is worth it to the organization. Personally, I think that the functionality you get in the VI3 Enterprise bundle–which includes HA, DRS, VMotion, etc.–is more than worth it. Is it worth having your workloads dynamically load balanced across all available physical hosts? Is it worth not having downtime due to a physical host failure, like I described above? Is it worth being able to move workloads from host to host on demand with no downtime? Again, that’s a decision you’ll need to make for yourself and your own organization.