A portion of a preview by USA Today:
One of the coolest new features of The Sims 3 on consoles is “karma powers,” where you can cast a spell, of sorts, to help your sim out in a number of ways. For example, does a pretty Sim like someone other than your own Sim? Use “Cosmic Curse” to the take out the competition by giving her suitor some serious flatulence. Is your Sim feeling down and needs a “Best Day Ever”? Everything will go right for your Sim as they go to work and get a promotion, and then come home to find an attractive neighbor at their doorstep. Each power only lasts a couple of hours, so be selective when and how you use it.
There could be side effects, too, such as morphing you into a monster at midnight by abusing the “Instant Beauty” power or taking away all your money after a successful day at the office.