You should be keeping tabs on The Sims 3, if only because it'll be cluttering up the PC sales charts for the next five years once it's released this June.
These new screens are meant to showcase a couple of things. One, that if you leave them alone, the Sims will still head out and do the stuff they love, like visiting museums, or the, uh, pool. The other, that you can make vampires in the game.