After five months of availability, OS X 10.9 Mavericks now generates just over 40 percent of all North American OS X-based Web traffic handled by ad network Chitika, almost doubling Mountain Lion’s current 21 percent share.
By comparison, the last-generation OS X 10.8 Mountain Lion took nearly 14 months to reach a 34 percent share and was only at 26.8 percent after seven months on the market.
As for older versions of OS X, 10.7 Lion and 10.6 Snow Leopard both account for 18 percent of Mac traffic, while OS X 10.5 Leopard is at 3 percent. The almost nine-year-old OS X 10.4 Tiger is still running on one percent of machines, while “other OS X” takes the last percent.