Bah. Logged in to vCenter today and it was running terrible and I couldn't get the vCenter services to start. Complaining of missing files. CPU was pegged but nothing was really busy. I finally took a look at the vSphere host and could barely log in...I rebooted it and found it wouldn't boot off the USB thumb drive. Looks like the drive failed at some point last night. This happens to be the one host I have with an internal 2TB drive so I reinstalled vSphere to that and it's running fine now.
Annoying.
Annoying.