Apple doesn't remotely "own" the high end of the PC laptop business. They're doing very well among web developers, so to a poster here maybe it seems that way. They're merely the largest single manufacturer among a very long list of PC vendors.
And the bit about "bargain" vs. "high end" presupposes there are features there that justify the distinction. A $99 tablet isn't going to have a 4G modem (though it's unclear if Apple's $300 item will either), but beyond that and its physical size the current Nexus 7 is a very feature-comparable device to the retina iPad.
That's pretty spun. It's true, of course, but by excluding the $950 laptops of other vendors (which are spec-wise very comparable with the Apple offerings) as "not high end" it's mostly just true by construction.
A similar number for "total units of 15 inch laptops with 4+GB memory and discrete GPUs" (my personal guess at a "high end" definition) would tell a very different story.
And the bit about "bargain" vs. "high end" presupposes there are features there that justify the distinction. A $99 tablet isn't going to have a 4G modem (though it's unclear if Apple's $300 item will either), but beyond that and its physical size the current Nexus 7 is a very feature-comparable device to the retina iPad.