After getting into a heap of hot water over the DRM included in the hit life simulation Spore, it's probably a wise decision for EA to back off a bit for their next major wide-audience release. Sims division executive producer Rod Humble posted a message on the Sims 3 website yesterday, putting fans' minds at ease.
The game will have disc-based copy protection – there is a Serial Code just like The Sims 2. To play the game there will not be any online authentication needed. We feel like this is a good, time-proven solution that makes it easy for you to play the game without DRM methods that feel overly invasive or leave you concerned about authorization server access in the distant future.
While personally I was hoping they'd go back to the old "what's the 7th word in the fourth paragraph on page 26 of the manual?" method of copy protection, I suppose this will have to do.
The Sims 3 Copy Protection [Official Website - Thanks Paradox!]