Only the person costs associated with the configuration/management of the servers - not the people time associated with the code, and high level system administration (which you still need with AWS).

I.E. The people who bought the servers, racked the servers, went down to the CoLo at night, set up the virtualization environment, hooked up the routers, configured the routers, the switches, the firewalls, the vlans -- those people I am including.

I'm not including the DBAs who manage the schema, people who push the code, do the design, etc...