"iPad mini gives you most of an iPad at half the size"

Here is MacWorld's very thorough and informative iPad Mini review. It has a lot of comparison data to the other iPad models and Apple devices.

The result is a device that—far more than the Mac mini, or even the old iPod mini—gives you nearly everything of its non-mini namesake in a smaller package.
But calling it “just a smaller iPad” glosses over much of what makes the iPad mini unique.

iPad Mini is even thinner than the iPad