For the best source of info on your question go here -
http://atccti.com/
Register and go to the forums, it is probably one of the best sources for ATC CTI info on the web. There are a lot of very knowledgeable people on there about the CTI program, the site was created by a CTI student who know works as a controller. For people like myself who work for the FAA we are very far out of the loop on CTI info.