Source of major confusion is the author is confusing an attempt to quantify install base with market share.
Definition of market share: "Market share refers to a brand's share of the total sales of all products within the product category in which the brand competes. Market share is determined by dividing a brand's sales volume by the total category sales volume."
Given that, web analytics aren't an accurate measurement of market share or install base, except to note that the majority of persons who access the monitored web sites use Windows machines. Extrapolation beyond this is difficult to certify, and concluding that the results of such a survey are conclusive, is disingenuous.
So, the author was apparently confused, and thus he has confused you. And all claims to the contrary of Apple's success is diminished by the fact that Apple is continuing to grow their market, grow their install base, and make inroads in the popular consumer electronics market with iPods, and the soon to be iPhone. Apple Deniers are in the same boat as Democrats when it comes to denying the success of someone just because their politics or their operating system disagrees with your own, their own tastes.
Macs work. Apple makes lots of money. Move on... Seriously.
