We used NPS when I worked at Carphone Warehouse.
We followed up calls with a 50/50 mix of text/voice surveys directly linking the scores back to the agents who took the call.
Results where delivered at agent, team & department level with both agents & managers targetted & commissioned on their scores.
We found NPS to be a great way of paying bonus based directly on customer feedback - my main advice would be to ensure you fully understand the NPS principles and communicate this effectively to staff before introducing the measures.
Whilst NPS was a great success in improving customer satisfaction there was the inevitible lack of understanding from agents resulting in complaints that they had no control over issues relating to policy/procedure and felt they shouldn't be penalised for a low score resulting from a customer who was unhappy with said policy/procedure.
There is an awful lot of info out there:
http://www.netpromoter.com
http://www.theultimatequestion.com
http://www.satmetrix.com/satmetrix/netpromoter.php?page=1