The desktop challenge began because we shared a common interaction in computing. There is not a right way to compute. It is no longer either or situation. Many people are checking all of the above: desktop, handheld, pad, set-top streamer.
We used to predict that the OS would become irrelevant. We really meant that the UI would become irrelevant. Users traversing their different devices may have accidentally become more sophisticated in their approach. This will give a real opportunity to the Chrome OS.
Even Linux users are not always using Linux. I use Linux on my desktop primarily (netflix) I doubt that there is 60% usage at the local LUG. Most Linux enthusiasts are sysadmins. Sysadmins are not necessarily power desktop users. The people that use Linux do not even need it. A geek can use anything.
I think a good subject (a blind poll) ask sysadmins that use linux in their networks, what they use on the desktop.
btw..if they ever figure out the Netflix problem..which could just be an alternative service, I would be filled with Linux Desktop Zeal again!