Back in December of last year I wrote about the gap closing between Microsoft’s 10 year old Windows XP OS and the new kid on the block Windows 7.  Windows 7 recently passed its 18th month of availability to consumers and the sale of over 350 million licenses world wide so it is no surprise that Windows 7 continues to gain on its predecessors and, in the US, finally slip by the old diehard Windows XP.

The following two graphs are based on data from

Source: StatCounter Global Stats – Operating System Market Share

Source: StatCounter Global Stats – Operating System Market Share

So on the US side there is not much else to add.  From here on out Windows 7 will continue to climb and Windows XP is on the decline.  That gap is quite small now but will continue to grow at a regular pace.

In the global arena the process of Windows 7 becoming the top dog is going to take a while longer.  Back in December 2010 the gap between Windows 7 and Windows XP was 24.73% and according to the charts above the gap is now 14.86%.  That equates to a 9.87% movement in 4 months.  Based on that history and the current gap it is probably going to be around October 2011 when Windows 7 catches and surpasses Windows XP on a global scale.  I think that would be quite a present for Windows 7’s 2nd birthday – don’t you?