This development isn't a huge surprise, if you're familiar with this chart, now a couple quarters out-dated:
Anyway, it's unclear whether it's really fair to say iPads are "PCs."
For me (the Business Insider news room is divided) iPads are, essentially, modern-day "home PCs." That is, they are not mobile devices nor are they work PCs.
People use them at home, not out and about, and not at work.
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