The article is taking one of two stances, but never formally (or clearly) states which. Either it's arguing that Windows is irrelevant because there is comparable software for no cost, or that the continued existence of Windows as an OS is pointless.<p>I'll freely admit that I host <i>all</i> my websites on a Linux machine. As a web server Linux is just better for PHP & Ruby. My development is on a Dell Studio 1555 with Windows 7, since I cannot afford the Mac price tag (I even got this one on a $150 off sale!).<p>But I still don't see why a $20 billion market is "irrelevant".<p>Now, that $20 billion is partly due to the fact of all the pent up demand for a working version of Vista. Remember that when ME flopped XP sold quite well... so it's not irrational to assume that W7 has prospered thanks to the failure of Vista.