ArsTechnica posted the latest operating system market share statistics. As of December, 2009, Windows is still the lions share of the market at 92.21%. macOS is a very distant second at 5.11% and Linux trails at 1.02%.

The trend is very slightly downward for Windows. It went from 93.66% in January, 2009 to 92.21% - a drop of 1.45%. At that rate it would take Microsoft 30 years to drop below 50% market share. But that rate won’t continue.

The trend is upwards for macOS, 4.71% in January to 5.11% - an increase of 0.4%. And its upwards for Linux, 0.90% in January to 1.02% - an increase of 0.12%.

Another way to look at this:

  • Microsoft lost 1.6% of their market share
  • Apple gained 8.5%
  • Linux gained 13%

So Linux is increasing market share the fastest while Microsoft is losing share. You can rack that up to the increased popularity of netbooks. Which, despite the press, often come with Linux outside the US and don’t get returned.

On the plus side for Microsoft, Windows 7 is a hit. It has easily outsold Vista for the same time period after launch. And, the market share for just Windows 7 is already larger then for macOS.

But, Microsoft’s biggest problem is the fact that 68.63% (slightly over 2/3) of all Windows installations are XP or earlier. Those installations don’t have a straight upgrade path to Windows 7. That high bar for migration - coupled with strong on-line applications - makes upgrading them open to alternatives, from super-cheap Linux netbooks to high-end Macs.

My guess is that we’ll see the overall market share of Windows drop at an increasing rate and that Linux market share will grow at an increasing rate while macOS will continue to increase at a modest pace.

And all of this doesn’t include mobile.