The Mini also has front- and back-facing cameras, for taking still photos and video and for videoconferencing. The Kindle Fire HD only has a front-facing camera for videoconferencing. The Nook HD doesn’t have a camera at all.
In short, the iPad Mini is more versatile than the competition, and I'm sure it will please a lot of people. But take a look at the competition first, and figure that by next year, we'll see something from Apple that looks a lot better.
Peter Svensson can be reached at http://twitter.com/petersvensson
About the iPad Mini:
The base model of the iPad Mini costs $329 and comes with 16 gigabytes of storage. A 32 GB model goes for $429 and 64 GB for $529. Soon, you'll be able to get versions that can connect through cellular networks, not just Wi-Fi. Add $130 to the price.