Apple describes Snow Leopard as a top-to-bottom refinement of existing features. One major goal of those refinements: Improved performance.
Snow Leopard aims to run leaner and faster on current and recent Macs, in part by dropping support for legacy Power PC systems and focusing solely on Intel-powered Macs. And while some of Snow Leopard’s potential performance gains won’t show up until software developers optimize their applications for the new OS, others are apparent right now.