(Update: for more, see "A closer look at the 2012 Apple iMac.")

Apple has unveiled a brand new, super-thin iMac at the company's showpiece launch event in San Jose this evening.

Marketing chief Phil Schiller pulled the cloak off the new device live on stage, which is an incredible 5mm thin - an incredible 80 per cent reduction on the previous iteration.

The iMac will come in a larger 27.in version at 2560x1440 pixels, and a 21.5in version with a 1920x 1080 display. It boasts a full lamination design with 75 per cent less reflection.

Other specs include an Intel Ivy Bridge Core i5 or i7 quad-core processor, up to 32GB Ram, up to 768GB flash, 128GB flash storage, a NVIDIA Kepler graphics card, an SD card slot, four USB 3 ports, and two Thunderbolt ports.

Pricing ranges from the entry-level 21.5in iMac at£1,099, to the £1,699 price tag given to the high-end 27in version.