Apple not only released the iPad mini but also a brand new iPad 4 to sit on top of the tablet food chain. It's got the new Apple A6X processor, the new Qualcomm international LTE radio, and the new Lightning connector.
Does that chance the comparison much when it comes to the competition? Absolutely but not entirely. Google is rumored to be introducing a new Nexus 10 (made by Samsung, no less) as soon as next week. That's make for a much better comparison than the only current Nexus tablet, which is more in between an iPod touch and iPad mini in size and focus. Amazon has also just released the Kindle Fire 8 HD which now includes cellular data as an option -- though it won't be available in many countries regardless.
Microsoft's Surface RT is a wildcard here. Microsoft calls it no-compromises but that just means they punted the decision making to me, the consumer. I'm taking a wait and see attitude. It could be as great as the Xbox, or as doomed as the Zune. There's just no way to tell until it's been out for a while and the use case becomes clearer.
Likewise, while there have been rumors of a larger BlackBerry PlayBook for a while now, RIM is wisely concentrating on getting BB10 out the door, so I doubt we'll see it for a while. That leaves the 7-inch PlayBook at their only entrant in the tablet space, but you can find them for $149 and at that price, if you don't have a couple hundred dollars more, it's quite the value.
Still, Apple has sold 100,000,000 iPads to date, and that's an incredible amount for a product that launched in March of 2010. What they'll do next is a big question, but the iPad 4 is a better iPad, again, and anyone who wants to unseat it has their work cut out for them.