Anticipation is now mounting over what Apple's announcement will be this Wednesday, amongst the rumours of new versions of iLife and iWork, and the promised sneak peek at the new Mac OS X 10.7 Lion's features, some reports are emerging that Apple may be set to unveil a new MacBook Air.

Last updated in June 2009, the MacBook Air is long overdue an update.

Apple Insider has published a list of potential features of the new MacBook Air. That title claims to have heard reports of both a 11.6in and 13.3in version of the new MacBook Air.

Reports also suggest the new device will "will do away with existing options for a conventional hard-disk drive (HDD) or solid state drive (SSD) in favour of an "SSD Card" that lacks a traditional drive enclosure and more closely resembles a stick of RAM.

In addition, Engadget has posted an image of a possible new MacBook Air.

As well as suggestions that there will be a 11.6in model, Macworld has heard reports that the new case will be made from a lighter magnesium alloy.

Everything will be revealed at Apple's Back to the Mac event on Wednesday 20 October at 6pm UK time.