Apple has launched a new 17in MacBook Pro in a low-key keynote at Macworld Expo in San Francisco.

The Mac-maker has used the event to announce several breakthrough products in previous years, but this time around Phil Schiller, Apple's senior vice president of worldwide product marketing, had few aces up his sleeve.

However, Schiller claimed the new laptop is a major breakthrough. First off, it's the world's thinnest and lightest 17in laptop - weighing 6.6lbs, and measuring just 0.98in - according to Apple's calculations.

Apple also said the battery installed in the new machine is its longest-lasting ever. With discrete graphics installed, owners of the new MacBook will get 7 hours of battery life. Those with integrated graphics can expect up to 8 hours.

See all MacBook reviews

The MacBook doesn't use the same cylindrical AA cells that most batteries do. Instead it uses custom-shaped cells. The lifespan of the cells is said to be triple the industry standard.

The new system includes up to 8GB of memory and has a 320GB hard drive as standard. A 256GB solid state drive is available as an option. It also includes a 1920x1200 LED backlit screen offering a 700:1 contrast ratio. The MacBook will start shipping in the US in late January from $2,799.

Schiller started proceedings by informing the audience that 2008 was the biggest year in Apple's history for Mac sales, with 9.7 million Macs sold worldwide. He said Mac shipments grew over twice as fast as the rest of the industry.

He also discussed the success of the company's Apple Stores around the world, with its global network of retail outlets expanding last year to include a store in Beijing. He said 3.4 million customers visit an Apple Store around the world each week.