I also think that Apple should get really nervous about the Nexus 7.
Apple isn't in any immediate danger (I've just plunked a ton of coin into AAPL) but it shows that competitors, primarily Google, are putting out high quality devices that work wonderfully and do not require a PhD to operate. That's always been Apple's strength (Microsoft could never do it) but now there appears to be real competition. History will remember the Nexus 7 as an industry changing product.
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