It does everything the SIXAXIS does and adds rumble. The SIXAXIS does not have rumble. That's the fact part.

As for my personal opinion, it just feels better too. The SIXAXIS was way light and always felt cheap. You can actually see through it if you hold it up to the light. The DS3 with the rumble motors in it is naturally heavier, but the plastic itself is made of sturdier stuff. You can't see through it.

Sony has actually discontinued the SIXAXIS (meaning they don't make it anymore, so once current supplies are gone they will not be replaced) so the DualShock 3 is the official Playstation 3 controller. I really don't understand why they haven't stuck it in their 40GB kits yet.