According to tracking from ad network Chitika, the latest version of OS X is already installed on over 10 percent of Macs accessing the Internet, a reliable measure of the active user base. The figure comes only one month after the launch of Mountain Lion, meaning the OS version is well ahead of Lion penetration at the same point in its release schedule. Currently, Snow Leopard still has the largest share of Macs, followed by Lion and Leopard.
