After a slip on Apple's UK site that revealed the date early, Apple has now officially confirmed that Mac OS X v10.6, known as Snow Leopard will go on sale Friday 28 August.

Apple's online store is now accepting pre-orders for the operating system that will be available as an upgrade for Mac OS X Leopard users for £25.

"Snow Leopard builds on our most successful operating system ever and we're happy to get it to users earlier than expected", said Bertrand Serlet, Apple's senior vice president of software engineering.

"For just £25, Leopard users get a smooth upgrade to the world's most advanced operating system and the only system with built in Exchange support".

Also available will be a Snow Leopard "Family Pack", a single household, five-user license for £39. For Tiger users with an Intel-based Mac, the Mac Box Set includes Mac OS X Snow Leopard, iLife '09 and iWork '09 and will be available for a suggested price of £129.