But is this gadget worth buying?
If you already have an iPad
Then why get a new one? If you have an iPad 2 or 3rd-gen, don't get the iPad mini unless you find it particularly appealing for your usage style. For example, if you are a frequent commuter and really see the big advantage, you can go ahead and buy it. It's your money. But personally, I feel like the iPad mini is a huge downgrade even from my iPad 2. It does not have the same power and it's missing the Retina Display.
If you are an original iPad owner, you may want to upgrade to a 4th-gen model or the iPad mini if you find it compelling. Also see this post.
As a standalone product
iPad mini is a cool device. It's convenient to read books on and makes for a very good web browsing device, it seems. It is great for travelers and frequent commuters. It is extremely light and small and you can hold it with one hand.
However, I do not find it very compelling because of the price point. I was always doubtful about how a $199 or $249 iPad will work without competing away a part of the iPod touch market. Turns out, Apple thought about it and made it a $329 product. It's the sweet spot for a tablet like this, but it's a price that makes me doubt the need of a smaller tablet in their current line-up of mobile devices.
Conclusion
I would not purchase this iPad as it is right now. Sure, it runs all the apps and stuff, but the price is too high for what I get. Buy an iPad mini only if you find its small and light design particularly useful for yourself and if you think that the missing Retina Display and low-performance is a good trade-off, which I don't think it is for my needs.
For $199, you can get an 8 GB Nexus 7 (or a 16 GB version for $249). Sure, Phil Schiller may have made it look bad on stage, but it's a tablet that is getting pretty good reviews.