It's possible that the Linux desktop will never be anything more than a fad among geeky enthusiasts. If so, a growing swell of people appear to be much more faddish of late, as numbers from W3Counter.com appear to indicate.
Looking at the data, Linux clearly has a ways to go. But consider just how far it has come:
Linux went from 1.25 percent in May of 2007 to 2.02 percent in March of 2008. That is 61.6 percent increase in market share in nine months. [Put another way,] that is 82 percent annual growth in installed computers.
These numbers don't match up with similarly gathered data from Hitslink, which has Linux market share still hovering around 0.61 percent market share. But even Hitslink shows strong growth over time: 41 percent-plus growth since May 2007.
It's not a perfect way to measure adoption. It's highly fallible. But one thing does seem clear to me from the data: Linux on the desktop is growing. It may only be growing within a small class of users, but it is growing. But if my grandma can use it, perhaps that "small class" will grow, too.