The off topic topic has again raised the great debate - what actually constitutes a theme park?
Based on the above, I respectfully disagree with the assessment.
Firstly, let's set the scene and a few ground rules - I'm sure we all agree Disneyland is undeniably a theme park. Uncle Walt practically wrote the book (of course, utilising ideas of others), and Disney Parks are usually well regarded as 'theme parks'... however, to set the bar at "disney level" or "$100Million per attraction" level is a bit unachievable for all but the big guys.
Now - based on the definition above we take a few things - firstly - Disneyland isn't a park with a single unifying setting. It has different lands, but - each land DOES have a (for the most part) unifying setting.
Movie World certainly has different areas or lands, and each has a unifying setting or idea (although those waters have been muddied in recent times).
Dreamworld likewise had different areas or lands each with their own unifying setting or idea. Again, muddied waters more recently.
So, in my opinion - an amusement park is a collection of attractions, where each attraction is essentially 'plonked' into a space that will fit, with no thought given to the surroundings. You can certainly "theme" each attraction and give it elaborate props and styling and signage, but if it doesn't relate to the things around it, it fails as a 'themed land or area'.
This is where I tend to disagree with those Perth based fans of adventure world. Mostly, each attraction in it's own right is themed well to a cohesive theme, but those themes don't tend to interact well with the other things around it.
Sea World, on the other hand, does well to keep it's theme. It's a marine park, yes - but see, that's the theme - the unifying setting or idea is that of water, ocean, marine life, the "Sea". It does make one scratch one's head when looking at previous attractions like the Dinosaurs, and of course, not everything Nickelodeon is 'sea' themed, but they've at least made the effort to have spongebob related attractions (at least 4 by my count) along with a Nick-theme applied to their other kiddie attractions.
Wet N Wild (GC) is a hard one to answer, but it's usually easy to exclude them as "water park". Although they've tried to have unified settings for attractions in close proximity in the past (Extreme H2O zone, Calypso), lately its become a matter of 'plonking' wherever it fits.
Are the GC parks "well themed" theme parks? Not when compared to Disney. Are they theme parks? in my opinion (and with the above caveats) - yes.
So... over to you. What do you think makes a theme park?