The new game, four years in the making, is set in beautiful Sunset Valley, a town that has 67 simulated human residents. They are fascinatingly complex and have lives of their own; you can follow them around or spy on them in their homes. All the residents age at the same rate as your character (a rate you can change to speed up the game). You can fall in love with the girl next door and marry her 10 years later. In previous versions, characters’ ages were frozen in time unless you were interacting with them.
article here (thanks for the find, SimOperations!)