Have you seen what you can get for $199? The Nexus has potential if you can get it and if Google bothers to support it. They typically hate dealing with actual customers.
The Kindle Fire and Kindle Fire HD are relative junk. Laden with in your face advertising. Doesn't even come with a power adapter. No volume controls even. No camera. Big, heavy, clunky, small display. Runs a heavily modified version of Android that's really just a Amazon sales platform. Can't get apps from Google Play, just Amazon app store.
And Amazon isn't even making money at that. No point in Apple trying to fight for that market.
I've never understood why Google wants to sell a tablet at a loss, or give away Android etc. I don't know how long they can keep spending money with giddy abandon without worrying about how they make money at it.
Folks are talking like the iPad mini is Soooo much worse than the Nexus 7. Are you kidding me? Its not that different, 1024x768 vs. 1280x800.
Due to Apple's software architecture, they can't make up arbitrary display sizes unlike Android. So their choices really were 1024x768 or double (4x pixels) at 2048x1526. They're trying to evolve that architecture but will take a long time with all the apps out there.