First and foremost, Cities: Skylines lets you make cities. No, I'm not being facetious. The biggest problem--well, one of the biggest--with EA's recent SimCity outing is that you could only really build towns. I mean, everything looked like it belonged in a city, but the maps were so constrained it was impossible to get that "major city" look.
When we booted up Cities: Skylines and only had a four square kilometer map to work with I feared we were in for more of the same. Then we found out that this was just the initial build space--you eventually earn enough money to buy nine of those tiles, for a total of 36 square kilometers. Sure, it's still "simulation size"--that's approximately 3 miles by 3 miles, or in other words smaller than the real-life size of a relatively small city like San Francisco.
It doesn't seem small, though. We were shown a late-game save where the map was packed with skyscrapers, and it was impressively dense.
Another nice touch: Those nine tiles don't need to be arranged in a square. The actual size of the map is five tiles by five tiles, so you can pick and choose which ones you want as long as they're touching. You could, for instance, follow the banks of a river or coastline.
You can also set up districts in your city and name them. You can set different civil policies for each district, ensuring that neighborhoods have a different feel just as they would in real life. For instance, you could set one district to have a high-rise ban, while another district embraces skyscrapers and becomes the de facto "downtown."
Cities: Skylines also claims to simulate every single person, the same as the most recent SimCity. Of course, those claims later turned out to be complete garbage in the case of SimCity, with the game simply fudging the numbers. I'm told that isn't the case this time around, but I have no way of independently verifying that at the moment.
All I can do is repeat what I was told, which is that the system is built off the same fundamentals as Colossal Order's previous Cities in Motion games. Those games relied on tracking every civilian in order to accurately simulate traffic, so the hard work was mostly done. We'll see how it works when there are thousands of people to track, but at least Colossal Order has a plausible explanation for why Cities: Skylines will work as advertised.
In fact, the only thing I didn't like about my time with Cities: Skylines is that buildings are tied to roads, the same as the recent SimCity. You lay out roads, and then zoning areas automatically appear. I assume this is because of the curved roads, but either way it's a bit of an annoyance.
However, the game makes up for it by adding in a complex water simulation system. Apparently Colossal Order worked with a research scientist on this feature, simulating dynamic water systems. That river in your city It's not just for show. Your city will actually get its water from upstream, and then flush its sewage downstream. You could probably do the reverse too, but I wouldn't recommend it.
You can even affect the flow of the water by, for instance, building dams to generate electricity while simultaneously drying up areas downriver. Unfortunately there won't be any disasters in the game at launch, so no building a dam and then destroying it to watch your loving populace die. You monster.
It's an ambitious title, for sure. I'd go so far as to say it's the SimCity I thought I was getting from EA. It's not as pretty, but I'll trade a tilt-shift effect for a deeper simulation any day.
And as a bonus: The game will have Steam Workshop support, and Colossal Order really means it. You'll be able to model your own buildings and all sorts of other wild things, so if you really want to make that one-to-one scale replica of Manhattan Well, you could. That's the opposite tack from EA's DLC-heavy approach to SimCity.
Competition is a great thing.