"Leopard, the sixth major release of Mac OS X, is the best upgrade we've ever released," said Steve Jobs, Apple's CEO. "And everyone gets the 'Ultimate' version, packed with all the new innovative features, for just $129."

Leopard is packed with more than 300 new features and introduces: a brand new desktop with Stacks, a new way to easily access files from the Dock; a redesigned Finder that lets users quickly browse and share files between multiple Macs; Quick Look, a new way to instantly see files without opening an application; Spaces, an intuitive new feature used to create groups of applications and instantly switch between them; and Time Machine, an effortless way to automatically back up everything on a Mac.

Note that Apple has updated their Mac OS X Leopard pages with updated content and a new look.

An image of Leopard's Desktop is shown below highlighting the new Stacks feature expanding upwards on the right.