Over at the Moscone West Conference Center in San Francisco at WWDC 2011, Apple's top Mac OS X men Phil Schiller and Craig Federighi took to the stage to officially show off Mac OS X Lion for the first time - despite the fact that it was previewed at an Apple event back in October and that developers have had their hands of the platform for a couple of months already.

Whilst up on stage the Apple bods gave us an overview of some of the new features that are packed into the new operating system including the funky multi-touch gestures, full screen app-ing, momentum scrolling, face-tracking tech and its pièce de résistance; the Mission Control option that lets you open apps, group apps, zoom and deal with your spaces in a more efficient way.

Federighi also showed off the Resume, auto-save, the integrated Mac App Store and Versions - which lets you keep different variations of your documents without clogging up your machine.

They were introduced on stage by Apple's top dog Steve Jobs and the Cupertino contingent were keen to stress that PC sales were down 1 per cent in the last year whilst Mac sales went up by 28 per cent, and that there were 54 million active Mac users in the world now.

A big potential customer base for OS X Lion then.

Finally the Apple gang got round to giving up the release details. For the first time ever, this is a Mac OS X update without a physical presence - it's a digital download only from the Mac App Store.

At 4GB in size it's around the same size file as a HD movie, will cost you £20.99 in the UK and $29.99 in the US to upgrade (Server will be £34.99) and it'll be out in July.

Take a look at Apple Mac OS X Lion: What’s new?

As well as our First Look: Mac OS X Lion review