About a month and a half since it's initial release, OS X Mavericks has already amassed a 2.42% share of the worldwide OS market. The data comes courtesy of Net Applications (via The Next Web) which measured OS marketshare for the month of November.
The latest market share data from Net Applications shows that November 2013 was a big one for Mavericks, which gained 1.58 percentage points (from 0.84 percent to 2.42 percent). All other OS releases lost share: OS X 10.8 fell 1.48 points (from 3.31 percent to 1.85 percent), OS X 10.7 lost 0.22 points (from 1.56 percent to 1.34 percent), OS X 10.6 slipped 0.07 points (from 1.60 percent to 1.53 percent), and OS X 10.5 dipped 0.01 points (from 0.33 percent to 0.32 percent).
All told, it's still a Windows world (assuming we're not counting the iPad as a PC) as various iterations of Windows account for 90.88% of worldwide OS marketshare. All iterations of OS X, meanwhile, account for 7.56% of worldwide OS marketshare. Impressively, Net Application's data indicates that 56% of all Macs are currently running either OS X 10.8 or OS X 10.9. In other words, most Mac users are running a version of OS X that is, at the most, only one and a half years old. As a reference point, OS X 10.8 Mountain Lion was released in July of 2012.