Wow, this is actually bigger than a lot of people realize, I think, in terms of where it may lead.
It will reverse the minority share of the computer market that Apple always used to have.
Of course, people will debate wether or not the iPad should count as a true computer, but the reality is, for the average person who surfs the internet and uses email and needs basic document making capabilities, etc., the iPad completely fits the bill... and it's power and capability will only increase over time.
Now don't get me wrong, the iPad has a few (but very large) limitations, but for many people, that won't matter. People who are not power users. And especially "old" people who are often intimidated by normal computers. There will always be a market for a "real" computer for power users and heavy duty content creators and serious gamers, etc. but as the day to day computing appliance, tablets have already begun to dominate, and they've only been out for a couple of years! (Not counting those big clunk "tablet" laptops).
Anyway, I digress, my original point was that this is big, and it's because it will increase Apple's general marketshare of computing devices, which will bring more people into Apple "ecosystem". It's a powerful gateway device.
Uhmm... no.
Windows has 90% of the world market. Apple... 7? +50% of surveyed people would prefer a windows tablet for a apple tablet. 95% of unsurveyed (i.e. me guessing) enterprises will prefer windows tablets to apple tablets. 95% of unsurveyed developers (i.e. more guessing) prefer developing for MSFT. So... no.
That said, Apple will keep raking money in for at least a few years to come. Well done on their behalf i must say. They deserve it. But no, they will remain niche (15% overall market in 2016 or so, a lot more of the profit share). In part by their own choice.
Of course, i could be wrong. But i doubt it. Then again, i wouldnt be that said if i turned out being wrong :- )
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The question of whether or not the iPad is, or is not, classed as a "PC" is largely one of semantics, and as such is increasingly irrelevant.
Companies, contrary to popular opinion, don't succeed or fail based on measures of Marketshare. They actually win or lose depending on how much money they make. And by that measure Apple is a very heavy hitter. Apple
makes more profit for each Mac they sell than HP does selling
seven PCs.
I know that many people have a strange aversion to profitable companies. I don't. While I like getting a "good deal" as much as the next person, I'm increasingly wary of technology companies who promise to give you the moon for nothing and make it up in volume. Such strategies are, I believe, ultimately either unsustainable, or carry with them such hidden costs in terms of loss of privacy (see Facebook) or outright theft (see Google) as to be both morally and commercially inviable.
Apple's product are, I believe, fairly and understandably priced. This has been their model with every product dating back to the first iPod and their first offerings on the iTunes store.
How much profit does microsoft make on those 7 HP pcs compared to Apple? Any figure... out of curiosity. And before people start ranting about apples and pears - so is in fact comparing HP to Apple.
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You're over-thinking it.
What might make it easier is to not try to understand it based on your *current* understanding, perceptions, prejudices. Drop the labels. They no longer serve to explain, but rather, to confuse and obfuscate.
Just accept the situation and see where it leads. There really is no need to question it, unless by not doing so your CPU will melt. Which it won't.

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What I feel, what you feel, what Knight feels, is ultimately irrelevant. The rightness or wrongness of the situation has no bearing on what is happening going forward. It's fun mind-play, but ultimately inconsequential. It doesn't lead anywhere.
Some folks here are struggling too hard to understand. Perhaps a tacit acceptance of the situation is in order.
You or I don't decide the direction of the market. Of course, you're entitled to your opinion, same as everyone else.
Part of the problem is all these bicycle/motorbike/car analogies. They aren't helping and they don't apply.
Oh the inconsistency. You're arguing for dropping the labels, yet you want to include your beloved ipad in a specific label. Which way are we going to have it, dear sir? Are there labels or not? Are they useful or not? If not, why not compare ipad sales to grape sales? After all, labels suck - right? On the contrary, labels are what makes the world go around - or knowledge, really. No labels, no knowledge. Simple as that.
Sure, include the ipad all you want. End effect: We need a new measure that does not include it. If the figure is relevant, its relevant. Apparently, for many, it is. Simple as that.
(And yes, if for some reason it stops being relevant in the future - it'll stop being relevant. But we are - obviously - not there just yet.)
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First, iPads are personal computers.
Second, if more than 2% of the consumers who are thinking about buying a personal computer starting walking out of Best Buy carrying Rice Krispies instead of a desktop PC, the industry would start worrying BIG TIME about whatever they decide to call that market segment.
Fact is, far more than 2% of Dells customers don't use their personal computers for anything that isn't available from the iOS App store. And consumers are catching on, even if they don't know the technically correct name for what they are buying (billions of dollars worth).
If i go into a car store, thinking about buying a SUV and come out with a town car. Does that mean a town car is a SUV? No. Your point?
X being able to replace Y does not imply that X equals Y. Doesnt matter if X is towncar and Y is SUV or X is ipad and Y is imac. A tomato will never become a cucumber. They're both vegetables though, and both quite tasty at that.
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iPad's are computers, the same way that Mac's are PC's (those Mac vs. PC ads really grate my cheese).
1. An electronic device for storing and processing data, typically in binary form, according to instructions given to it in a variable program.
However, using that definition, Samsung is the world's largest "Computer" maker. I mean, Televisions, DVD players, Video cameras, non-smart phones, ECU's for car engines, are all computers.
And thus, we can conclude, there is a discrepancy between the official definition of the term, and the interpreted, real-life, meaning of the same.
Is the ipad personal? Yes. Is the ipad a computer? Yes.
So?