True enough. I'm only speaking from my experiences over the past year. You are obviously seeing something quite a bit different than I am. Although you forgot to include Windows NT in there... NT4 SP6A was nice and stable.
For individuals, the choice of OS is related to the relatively standard programs they run - games, browser, email, office.
For corporations, the choice of OS is related to other applications as well - finance, manufacturing, planning, storefront, and more. If those aren't compatible, it's not worth the effort to move up until the infrastructure supports it. Duplex printing didn't work on my HP printer for six months after Vista was out. For me, it was an inconvenience. For a company with 250 PCs and 25 printers, it would be much more than that.
And since Cerek's original question was about a (mostly) personal laptop, many of my points will simply go away...
