When it comes down to it, Orlando is a service economy with mostly low wage jobs. The people who make the tourist industry possible can't afford to enjoy the attractions on a regular basis. SeaWorld Orlando is offering them a theme park experience they can afford to take their families to. Regional theme parks like Six Flags/Cedar Fair/SWP&E will always have a market because not everyone can afford the Disney/Universal experience all the time, and they do offer some things that Disney/Universal do not, particularly in the realm of thrill rides.
SeaWorld's new strategies combined with the lack of Blackstone's bloodsucking is paying off, and having a management team who actually knows the parks from the top down will continue this streak.