I know I'm parallel-commenting here the guy himself, but seriously, I believe this is just what happens when you either have too much money, are too lazy, or both.

I am pretty sure they could have come up with a basic MoBo+GPU+CPU+RAM combo to buy from a large distributor, assemble them in series in no-time and get a vastly cheaper and more powerful farm.

Walking around buying mac minis a dozen a time to build a data center is just silly in my opinion, whatever the reasoning.