Let's get down to brass tacks. Nobody says you have to buy an Apple computer (and the author of this post points out that he doesn't have one). We're done here, right? Not quite.
Picking through the ranting what I think I see is someone who's upset about Apple's success and what they're doing with their market inertia. It was pretty much a given that if the App Store for iOS took off there would be an App Store for OS X. If we were in a pirate movie right now we'd call that a "parlay." Apple has done a lot of things right if your metric is strictly financial success. Where people seem to be incredulous is that (although highly subjective) Apple has also done a lot of things right when it comes to user/consumer experience. Nerds are not the primary audience for Apple's products. My parents, grandparents, and people who are more interested all things non-technical are. An App Store on OS X (and the existing one of iOS) is good for the two parties most important to Apple, normal users and Apple.
If you feel strongly about how this has shaken out then I challenge you to ask yourself, "why?". There are tons of ready-made excuses along the lines of "openness", "freedom", and "I don't like guys in turtle necks." None of them really matter. The problem of how non-technical people find and install computer software is decades old. As designers and developers we've largely left that problem to platform developers, sales, and marketing people. Now someone has come along and placed a viable solution into the mass market all while creating the potential to make a tidy profit. We call this capitalism.