No, there won't be one. I don't have any official or insider information, but it makes complete sense when you think about it.
All of the items that people are talking about are either minor (nighttime mode, fireworks, new rides, etc.), or require a conversion to 3D.
The culmination of minor upgrades will not be released as RCT2. If they do get released, they will be yet another $30 add-on pack.
RCT will never officially be converted to 3D either. Chris Sawyer has never written a commercial 3D game, and he certainly won't start with something this complicated. All of his previous games (RR Tycoon, Transport Tycoon, etc.) all used the same basic 2D isometric engine. He's not going to do a 180 and create a 3D engine for these games.
To properly convert RCT into a 3D world is extremely complicated. I know, because I'm writing a 3D viewer for RCT parks. To do it right, the user would need a 1.7ghz chip, and a geforce3, but there would still be imperfections and anomalies.
For example, look at games like Ultra Coaster and No Limits. They can suffer from low framerates, and they are relatively simple games. The coasters are simple curve-based objects, with polygons as supports, and a handful of other objects (trees, station, sky). RCT is infinately more complicated, with many different textures, buildings, rides, track types, etc.
How many times has this been asked? Check the search function, you might find a lot of opinions that way.
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Do your own homework!
