At first glance, Mountain Lion looks like an identical twin of its predecessor, OS X Lion. Upgraders from Lion will face an almost flat learning curve, because almost every feature they've learned to use works in almost exactly the same way as before. But Mountain Lion unobtrusively slots in dozens of new features—Apple counts two hundred of them—that enhance sharing, messaging, cloud-based synchronization, security, Web browsing, instant notifications, and accessibility.



Link: Techreviewsource