Steve Jobs may be the undisputed grand master of technology hype, but when it comes to numbering operating systems, he’s oddly self-effacing. With Leopard, the new version of OS X, Apple has nudged the version number forward from 10.4 to 10.5. Most companies would assign such a teensy increment to an update with a few minor bug fixes, but Leopard includes more than 300 new features by Apple’s count. Even after you weed out several dozen pieces of ephemera such as Kerberized NFS — if you don’t know what that is, you’ll never need it — the US$129 Leopard is a big deal with plenty of meaningful enhancements over its predecessor Tiger.
http://www.slate.com/id/2177073/