There are several aspects: There are bragging rights, there is reality, there is sale numbers.
For bragging rights, iPad sales obviously need to be included. On the other hand, Apple would probably prefer if nobody told Microsoft, Acer (who seems to have suffered most from iPad sales) and others what is going on. I think Apple is quite happy making loads of money while Gartner tells the world that they are not even in the top five in world-wide computer sales.
There is reality, which tells us that Apple is selling an awful lot of devices with large screens that are used for things that people used to use a traditional computer for. This is like asking if we should count Blu-ray sales under DVD sales; we shouldn't if we want to know about DVD sales, we should if we are really interested in movie sales. And these iPads are not exactly cheap; there are an awful lot of so-called computers that are actually netbooks that are a lot less useful and a lot cheaper than an iPad. And the iPads do take away PC sales, so they are in the same market. Like DVD and Blu-ray: Not the same thing, but the same market.
And then there is the question of the Microsoft OS monopoly. We can take the number of interesting computing devices, and check what percentage of those has an operating system that is not a Microsoft operating system. And I would count desktops, laptops, netbooks, and all tablets under "interesting computing devices". A year ago it was almost completely Microsoft, with a small percentage of MacOS X, a tiny percentage of Linux, and an even tinier percentage of others like Solaris. If we look a year ahead, there is still a small percentage of MacOS X, a tiny percentage of Linux, and an even tinier percentage of others like Solaris, but a quite considerable percentage of iOS and probably a reasonable amount of Android as well. I can easily see 15% percent of non-Microsoft OS on computing devices sold this year, and 25% next year, especially if you consider that many of these iPads and Android tablets will mean fewer netbook or laptop sales with Windows.
Yet more evidence that iPad sales should not be included in the comparison. It just doesn't compete significantly with desktops and laptops.
Look at Acer's sales. They sold a shedload of netbooks the year before, and then came the iPad and destroyed it.
The same could be said about netbooks.
Again, the same could have been said about netbooks.
People were complaining all the time that Apple wasn't selling a netbook. Let's try to think logically: Apple still doesn't sell a netbook. If the iPad is a computer, then this is fine, because the iPad can be viewed as an alternative to the netbook, and one that sells very well. If the iPad is _not_ a computer, then everyone should still be complaining that Apple is _still_ not selling a netbook. Has anybody heard these complaints in the last year since the iPad was released? I haven't. So it seems that the world has actually accepted that the iPad is a computer.
