Hey Darius, happy new year!
It is indeed on a 6,2 mac mini with the not-entirely-official engineering fix for the ESXi+Macmini6,2 SMC problem.
The error I get is "OS X Update can't be installed on this disk. This volume does not meet the requirements for this update."
I tried the 10.8.1 update, and got the same error. I have tired the built in software update, but it just says "There are no updates available"
Maybe I need to just make a new iso and do a new install.