Just-released data from Net Applications shows that Microsoft’s share of the PC operating system market continued its slow decent in October as Apple’s Mac operating system and Linux both showed narrow gains. While Windows is still the overwhelming market leader among desktop operating systems, the platform slid from a 92.44% share in September to a 91.86% share last month. Over the same period, Apple’s Mac OS climbed from 6.45% to 6.94% while Linux inched up from 1.11% in September to 1.19% in October. Microsoft’s share of the computer OS market is expected to continue its slow decent until the second half of 2012, when it is expected to launch its next-generation Windows 8 operating system that marries a full-blown desktop OS with a light-weight mobile platform for tablets and other emerging devices. A chart illustrating October desktop operating system market share data from Net Applications follows below.