I believe this is a case of self-confirmation bias.
Checking for similar articles from 2003, around 2 years after the launch of XP, I found this gem: "Windows XP, the most current version of Windows, was found on just 6.6 percent of the [business] machines" (http://www.zdnetasia.com/news/software/0,39044164,39161686,0...).
To be relevant, you'd need to consider this against XP's adoption taking into account rate of machine turnover.
Few people actually upgrade OS.
Yes, this means there hasn't been a compelling reason to upgrade OS. But that doesn't mean that much. There hasn't been a very compelling reason to upgrade machines in general.
It might signal that MS were solving problems with Vista (security mostly) that didn't really exist.
Checking for similar articles from 2003, around 2 years after the launch of XP, I found this gem: "Windows XP, the most current version of Windows, was found on just 6.6 percent of the [business] machines" (http://www.zdnetasia.com/news/software/0,39044164,39161686,0...).