A host of changes are coming to the series. For starters roads can now be curved, making for more organic city layouts than the grid framework the series was known for. The fixed viewpoint is also gone, allowing players to zoom in on specific buildings or move the camera around. Zooming in close to the ground also changes the audio, with close ups providing the cacophony of the city, and zoomed out views providing a much quieter atmosphere.
Buildings will have tiny pieces of signage, individual citizens will roam around and go about their daily lives, sometimes doing benign things like going to dinner, other times becoming proactive and protesting if jobs get low. The attention to detail actually has gameplay importance too, as you can see if a factory is working effeciently based on how it looks, how it animates.
Buildings also change over time in SimCity, unlocking new abilities, such as the power to put out fires faster for an upgraded fire station.
