Not smaller, but the newer style is more squared, the older more rounded.
The single biggest thing I LOVE about the newer one is that the third row seats fold flat at the touch of a button, and these seats are full size, and comfortable for an adult.
In the 2000 model, the third row seat sits up quite high, leaving very little head room. And getting that seat out of the way mean wrestling it OUT of the truck and storing it in the garage.