I'm retired military (best decision I ever made was to stay in until retirement). Don't get out thinking the grass is greener on the other side. Some quick pros/cons on AirTran from my point of view.
Cons:
- Hostile work environment (very hard to adjust to after excellent leadership in military).
- Very poor/inefficient management (if we get a competative contract we will no longer be able to compete against Southwest and JetBlue).
- Inability to weather another economic shock (we were hours from bankruptcy when oil went to $140/barrel). A new contract combined with another economic shock will cause the Tranz to fold like a circus tent (we are not to big to fail like Detla/United/American).

Pros:
- Better place to keep currency than the regionals (they treat you poorly here, but at least you're paid better than starting regional pay).
- Good company contribution into plan B fund (but only vested after 3 years).
- Very good training department, but that may change when AQP is forced on us by FAA.

Once again, if you already have a good gig don't leave it for AirTran.