Last year, after the iPad mini update, John Gruber (along with many, many other people) came to this conclusion:
Last year, the iPad 4 and original iPad Mini felt like two different devices. This year, the iPad Air and retina Mini feel like two sizes of the same device — more like the difference between the 11- and 13-inch MacBook Airs than the difference between MacBook Airs and the MacBook Pros. If anything, the new iPads are even more similar to each other than the 11- and 13-inch MacBook Airs are. Again, I’m pretty sure the only differences between the new iPad Airs and Minis are size/weight and $100.1
And later, after spending more time with it;
Just one year ago, those were the compromises Apple was forced to make. They could shrink the year old iPad 2 into the Mini form factor, or go retina and A6X with a thicker and heavier battery.
This year, there are no compromises, there is no or. The iPad Mini has gone retina and provides just a hair less than the full performance of the Air, with no appreciable increase in weight or thickness over last year’s Mini.
Hence, I think, the name change for the 9.7-inch model, from last year’s “iPad” to “iPad Air”. There no longer is a main or regular or standard iPad. Last year Apple billed the Mini as “every inch an iPad”, and that was true, but it was every inch an iPad 2. This, year, it’s every inch a top-of-the-line iPad.
That's what was so frustrating about yesterday's keynote - it wasn't that the iPad mini is a second class citizen, it's that it already had been. Apple took the form factor and went backwards.
I don't know exactly what prompted this, but a reasonable guess is that shrinking down the iPad Air 2 proved unfeasable right now probably due to conflicts between the new A8X processor and the battery. Instead of releasing an iPad with 9 hours of battery life, they waited until next year. But why not just use an A8? It's already smaller, and more powerful than the A7 - they told us as much and we've confirmed it since the iPhones 6 have been out. The A7 (no X) was good enough for the Air AND the mini last year, what's with the jump back to having to boost the graphics of already the best graphics processor shipping in a mobile device today?
They could just be trying to move everyone back up the price chain, away from lower margin products. I imagine they make more off of every iPad Air than the mini. That's definitely the skeptic's version of events, but it's definitely possible.
I'm a big fan of the mini over the full size form factor - I've owned both, and after using the mini i couldnt fathom going back to the full size, even finding the larger Air almost comically large after just a few weeks with the new device (think of it as the opposite effect of the iPhone 6 - one week with that and my iPhone 5S felt like a child's toy).
As for what the future of the form factor looks like, I don't think any of Apple's existing second-class products are any indication of future behavior in this case. I doubt it will languish like the iPod touch (still an A5 processor, in case anyone was wondering), or behave like the Mac mini, because I can't conceive of a product under such high scrutiny going a year without an update, at least not yet. I also don't think that it's in danger of elimination, but that's a lot harder to prove.
Now, I don't really know what I'm supposed to do. My biggest worry about the iPhone event before it happened was that I was going to be presented with having to sacrifice mobility for power; that the iPhone 6 Plus was going to be markedly more powerful and feature rich than the 6, and that I would have to take a decided drop in functionality in order to have a phone in the size I wanted, or force the transition to a bigger phone (which I'm still glad I don't have, by the way) in order to get the best features. Even though the Plus has the slightly better camera (nothing different about the lens itself, but with the addition of Optical Image Stabilization, as opposed to the 6's Digital IS) and more battery life (becase of more room), I don't believe I was forced to make that choice, which I was very happy about. With these new iPads, I'm clearly having to make that choice.
I have a T-Mobile JUMP upgrade for the current retina iPad mini, which basically means I can trade up for either iPad with no up front cost. If I get the mini, what I'm trading up for is the same iPad I have (and love), with Touch ID and twice the storage for the same price. My thought is that that's probably what I'll do: there are very few features that would cause me to abandon this form factor, and none of them are in the iPad Air 2.
If you're just tuning in, differences between this year's two models are "better display, more RAM, upgraded processor, upgraded motion coprocessor, more LTE bands, 802.11ac wifi, and a new, thinner design for $100" ↩