We are big on SLAs. Department directors have to sign off on an SLA before IT will support their stuff. Actually this is how IT gets it's budget.
For example, marketing comes to IT and asks for a service like sales tracking. After figuring out what they want we give them a quote with SLA and how much it will cost. After buildout there is a sign off and the service is available for use. To the users there is no concept of hardware of server. They just know if their stuff is working or not. I mean they are marketing people. Any problems that occur are tracked by our ticketing system, and its just a matter of tracking resolution time, incident severity and number of incidents. All of this is defined in the SLA. Resolution time usually comes into play when looking at service availability, and in the incident review process for high or critical outages.
For our team individual performance usually comes down to how well we contribute to the team. My review is not that much different from a kindergarden report card. "Plays well with others" is now "Maintains positive relationships with external partners"