Thanks for the link.  It's good info but seems to be a different issue than what I'm seeing.

What I'm going to attempt next is to install the latest patches on my ESXi servers. I will report back if it helps.

Finding it extremely hard to believe that OVF deployment via the web client doesn't work at all on 6.5 vcenter, I don't know if this is just something specific to my own setup or if everyone is seeing this behavior.