The game sold a record 1 million copies in its first 10 days.
The neighborhood in the game called Veronaville is a reference to William Shakespeare and his plays "Romeo and Juliet" and "A Midsummer Night's Dream". All of the people who are originally in this neighborhood are characters in one of those plays and their relationships are also how they are portrayed in the plays, such as the Capp and the Monty (Capulet and Montegue) families also don't get along just as it is in his tragedy "Romeo and Juliet".
It was originally intended that there should be rain in the game, but rendering errors kept making it rain indoors too, so it was scrapped. Rain, snow and other weather effects were added in the fifth expansion pack, Seasons, that was released in early 2007.
Casting calls were done in San Francisco and Los Angeles.