For those who missed the Slashdot article, Samba Team member John H. Terpstra has written a series of articles for searchopensource.com on obstacles to the adoption of Linux on the desktop. John offers a real life example to lead into his thoughts on the subject, which makes for some compelling reading.
So Linux desktop computers cost more than Microsoft Windows PCs do, and it's hard to find devices and drivers for Linux. Is that such a big deal? Well, in this story of just two Linux PC buyers, such difficulties stopped one from using Linux and the other only succeeded by being very persistent. Multiply that by millions of PC users, and you have a big deal.
For more see Part 1, Part 2, and part 3 of "Stopping Linux desktop adoption sabotage."