We don’t usually go out of our way to mention point-updates to Apple’s Mac operating system. Usually, there are few revolutionary new features to be concerned with; we figure most people will update whenever they get around to it, and be just fine until then. OS X Mavericks 10.9.2 (Free) is one of the rare instances in which we suggest going out and upgrading right away. Sure, there are a handful of new tricks, but security is really what’s…