How can you ask people to put critical servers in an virtual environment, but then not trust it enough to put your management servers in it?
You are much more likely to have a failure on a physical rather then a virtual. And if it dies you can rebuild a windows server and have vCenter up and running in no time.
This doesn't answer your question. I am not sure about any VMWare documentation that says it is best practise, but I have seen it encouraged.
The following is from the install guide
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Install vCenter Server in a Virtual Machine
You can install vCenter Server in a Microsoft Windows virtual machine, which runs on an ESX host.
Deploying the vCenter Server system in the virtual machine has the following advantages:
* Rather than dedicating a separate server to the vCenter Server system, you can place it in a virtual machine
running on the same ESX host where your other virtual machines run.
* You can provide high availability for the vCenter Server system by using VMware HA.
* You can migrate the virtual machine containing the vCenter Server system from one host to another,
enabling maintenance and other activities.
* You can create snapshots of the vCenter Server virtual machine and use them for backups, archiving, and
so on.
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