Snow Leopard builds on Leopard’s enormous innovations by delivering a new generation of core software technologies that will streamline Mac OS X, enhance its performance, and set new standards for quality. Snow Leopard dramatically reduces the footprint of Mac OS X, making it even more efficient for users, and giving them back valuable hard drive space for their music and photos. ( Edited by Devin )  

http://www.apple.com/macosx/snowleopard/