I could see America West or jetBlue making OKC their south-central hub someday. Once the OKC airport is finished with their renovation I'm sure they will be looked at. But the airlines are still recovering financially from 9/11 and won't be majorly expanding anytime soon.

Future service OKC needs:

United - San Francisco, Washington Dulles
American - Los Angeles, Miami
jetBlue - New York JFK
America West - Las Vegas
Northwest - Detroit
Delta - Orlando
US Airways - Philadelphia, Charlotte
Southwest - San Antonio, Albuquerque, Wichita, Austin, San Diego, New Orleans
Air Canada - Toronto
Mexicana - Mexico City

With Great Plains gone, does OKC still have non-stop service to Tulsa?