the iPad Mini with Retina Display means Apple can nudge consumers to buy the potentially less-popular iPad Air.

I'm going to go out on a limb and predict that the iPad Mini with Retina Display launch may be one of the most product-constrained to date for Apple.
The prevailing wisdom is that Apple can't get enough displays. There are enough credible analysts -- some speaking with CNET -- and reports that it's likely to be true.
Even CEO Tim Cook sounded less-than-optimistic about the iPad Mini Retina when he said last month that "it's unclear whether we'll have enough for the quarter or not."
In other words, it's more than just a convenient reason for Apple to stagger the release of the iPad Air and iPad Mini Retina.
But that actually isn't a bad strategy -- however unintentional. Launch both the iPad Air and iPad Mini Retina (the latter with hypothetical plentiful supply) at the same time, and the $399 Mini Retina could bury the $499 Air, relegating it quickly to an also-ran.
After all, the Mini has been doing just that: killing off the iPad 4.
So, here's one possible scenario: Apple announces later this month that it will make the iPad Mini with Retina Display available for orders. But, as expected, there are too few to go around. Meanwhile, the iPad Air, by comparison, is readily available.

So, Apple is able to partially satisfy a long-standing hunger for an iPad Mini Retina (consumers and analysts would howl in protest if it didn't), but it can also continue to nudge consumers who can't an iPad Mini Retina because of limited supply to the potentially less-popular iPad Air: "Hey, if you want a thin, light, Retina iPad right now, there's always the Air."
And that's not a bad argument, actually. I've been using the iPad Air since last Friday, when it went on sale. Though the iPad Air moniker may be a slight misnomer (the Mini is the real "Air"), the iPad Air does narrow the wide size-weight gulf that existed between the iPad 4 and the iPad Mini.
Before the iPad Air, jumping from the iPad Mini to the iPad 4 was a little like jumping out of a Ford Fiesta into a Super Duty F-350 Ford pick-up (a slightly exaggerated car analogy, but you get the idea).
So, I'll stick with my prediction about the iPad Mini Retina, but the iPad Air does make the wait a lot less painful.

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