Depends on what you mean by CTI
CTI is a very useful tool, and doesn't just have to mean 'screen-pops'. We use CTI for almost every client in out center one way or another:
1) Dialer: We have built an integrated preview dialer application on top of CTI and our ACD. This allows us to avoid having the agent dial the call, and we can attach data to the ACD call records that points to the customer record. So we can find out 'how long does a call take that results in a sale as compared to a not interested?'
2) Dispositioning: At least on Aspect, their built in dispositioning is pretty cruddy. It doesn't do any error checking and doesn't require dispositions. With CTI we can have a desktop app collect the dispositions for inbound calls (providing the agents with a drop down list of the only choices they have).
3) Scripts: We have a client with 35 different scripts depending on the phone number the person called into. With CTI, we just pop to the right script so the agent knows what particular product the customer is calling about, and in case of DRTV, which ad they even got the number from.
4) Multimedia blending: Our CTI server also controls our queuing for our chat program. So our agents can receive a chat or a phone call but not both at the same time (unless specifically requested).
5) And of course we do use screen popping, but not based on callerid because that is unreliable. We prompt the customer for their ticket # (this is a tech support line) and the agent is able to greet the customer by name and have their ticket up when they get on the line. This is important in tech support where people are already frustrated and they want to know immediately that they aren't going to have to re-explain themselves.
6) Future: We are looking at using CTI to truly integrate our ACD and predictive dialer systems so we can have the best of both worlds. I am still researching this.
Hope this helps.