Three years ago, I would have agreed 100% with this guy.
Today, Linux on the desktop beats the crap out of Windows (does all the same stuff but looks better and has more cool apps with cooler features), and it even has some apps that I like better than OSX apps (OSX apps traditionally being slick). Muine, for example, beats the hell out of the iTunes interface IMO.
Linux is just taking off on the Desktop. Until fairly recently, it's been playing catchup. For example, when Windows XP was released, Linux distros du jour had nothing on it. It's only recently that I found myself having no more apps wish-list. There was a good app to do literally everything that I wanted.
I'm very interested to see what happens in 2006. Apple's OSX 10.4 (10.5?) will be released right around the same time that Microsoft is releasing Longhorn. For the first time, Linux will be more or less on equal footing at the beginning of a Desktop release cycle, rather than lagging behind. What's more, Linux will be leading the pack, with the successors to Longhorn and OSX 10.6 being developed behind closed doors.