This game has come out some weeks ago now. It is a citybuilding game, brought up by Paradox and developed by Colossal Order whose base is mainly traffic management, but has deep mechanics in all its aspects. Basically it is a version of SimCity, but done in a better way. Let's see what things make it a better choice and, after all, a good game:
• Whereas SimCity simulates traffic and the life of your city by means of complex algorithms (i.e.: in a zone there are 100,000 inhabitants, so traffic is 70. If the road besides only holds a traffic of 60, that road jams), Cities Skylines simulates every person in the city individually (in fact, you can change their names, the names of their cars, etc.), and those people take their vehicles, and those vehicles, if they are too many, eventually jam the roads. This concept, yet leading to unrealistic situations, is to me awesome.
• MODS!: Yes, that's right: it is Steam Workshop compatible. In fact, you can not only make mods that modify gameplay experience itself, but also you can download through it communitymade buildings, plazas, road intersections... And if you are likely, you can also make your own to share them with the community! It is a fact that there will be always a person that spends more hours than you in a game, and with this system you can benefit from it, as you may find “perfect” intersections, or morbidly ideal city plans. This feature is one of the best in the game.
The only thing I see you would prefer playing SimCity is that, as mentioned, traffic and city planning in that game is much more realistic, that you can trade with your neighbours and, of course, multiplayer. But anyway, if you are a fan of city planning games, you must buy this one!