Theme Park Studio, as the name itself would suggest, is a collection of tools that allows you to design, build, and experience your very own amusement park... or torture chambers, all depending on what sort of stuff you're in to! It launched in Early Access back in 2014, and as a quick glance across the Steam reviews would tell you - it came with a clunky UI and more bugs than a freshly brewed Bethesda game.
Two years and numerous updates have passed since then, and it appears that Theme Park Studio is now finally ready to release from Early Access as the developers have pinned November 25th as their big day. While there is currently no launch trailer available, some of the previous gameplay videos should still give you a good idea of what Theme Park Studio is all about. Have a look:
Whether Theme Park Studio is any good or not, that I'm afraid is not an easy question to answer given how divided the reviews are. Many are citing problematic controls, general instability, and numerous issues with the core gameplay, while the other camp firmly believes that Theme Park Studio becomes quite amazing once you get used to its kinks. Whatever the case may be, I would suggest you wait for the official release and a fresh batch reviews before you make any sort of decision. To do anything else in this sort of a scenario would be downright silly, so try to have a bit of patience and simply observe how things pan out once Theme Park Studio actually releases.