It's a well-known fact that Will Wright loves robotics, and it even got him into the games industry. His first game, Raid on Bungeling Bay, was the first step towards the now famous SimCity. A few years later SimAnt was developed, which eventually turned into the people-simulator the Sims. Will talks more about that process, in an interview with RedAssedBaboon.com. He said the Sims would either by a smash hit or an utter failure - and as everybody knows now it became the first, even beyond Will's expectations. He also mentioned expansions for the Sims 2 being in the work right now, and even mentioned the Sims 3 shortly:

"Although a Sims 3 is likely, Wright was hesitant to talk about details, saying only that the Maxis team leans heavily on what they see the gaming community doing with their games to help develop a sequel."

Read the entire interview for all the details.