So, there's an official site for it now; The Sims 3.. Nothing more than a (part of a?) logo, for now, but promising more soon.. And then there's this; An Early Look At The Sims 3
Tuesday, March 11, 2008

Electronic Arts' Ben Ball recently provided an early look at some of the features planned for The Sims 3, the third iteration of the popular Sims series which allows players to control the lives of digital people. The Sims 3 will focus on offering a seamless environment largely devoid of load screens as well as a wealth of customization options for Sims creation and environment modification.
The first thing you’ll notice about The Sims 3 is that the Sims now live in a completely seamless, living neighborhood. This means that they can walk next door, walk down the street, drive to the center of town, stroll through the park, and explore everything without ever encountering a load screen. Wherever you go in your town, you will see other Sims going about their daily lives. You’ll discover new things about the community that your Sims live in, and you will have the chance to participate whenever and wherever you like. As a player, this is an incredible innovation for me because now I can see what my neighbors are up to all of the time and go interact with them. Or if I am feeling devious I can peek through the window and spy on their every move. I can even shoot across town to see what the other families in my town are doing, any time of day or night. It’s an entirely new way to play with your Sims!

The second aspect of The Sims 3 that always impresses me is our completely reinvented and realistic Create a Sim. In The Sims 3, you have so much freedom to create the Sims that you want to make, yet it’s easy and fun. In the coming weeks, we will have some screenshots on our website that show you a small glimpse of what is possible with Create a Sim. The Sims can look like anyone you imagine. I’ve made my friends, my great grandpa, and many other important people from my life. We also have a new realistic personality system called Traits that allows you to determine the personality of every Sim. There are dozens of Traits that you can assign to your Sims. Every Trait will change the way that your Sims feel, think and behave in the game. You can choose several traits for your Sims, so it’s really possible to make any character that you can imagine and they will come to life in The Sims 3. Now imagine placing these unique personalities into your very own “Petri-dish” that is the new seamless, living neighborhood.
The Sims 3 is expected to be be officially announced later this month. To read the rest of Ball's comments about the game head over to the Worthplaying site linked below.

Worthplaying: The Sims 3 Details