Great question, I don't know if this is the normal way they show a continuing flight or not. The way they print the boarding cards will probably be a factor.

More important to ATL flyers if the reminder to check for hidden cities. Even now, this trip is pricing cheaper MCO-ATL-OKC than MCO-ATL on the same flight.

The Southwest rules specifically allow hidden cities and AirTran is silent on the matter, if I remember correctly.

Always buy hidden city tickets one way, virtually no reason not to for either of these carriers.