I came here to mention that was the most stunning bit of the article. Not the fact. But that someone is using the size of the Linux market to demonstrate how large mainframe's share is.

I'm old and have lived through the growth of Linux. Starting as nothing, through all the FUD, and naysayer pudits, and claims it was communist, and MS many monopolistic attempts to squash it, etc. Comments like that still make my jaw drop.

... and we are talking about "market", that is about usage of Linux that involve exchange of money, no? So that's even more impressive.