We've been reporting on the possibility of the much-fabled ultra-ultra-portable MacBook for some time now. Regular readers might remember 9to5Mac had even claimed to have seen the new super-skinny machines.

They stated that the "Pro slimline" as they dubbed the device, was black and silver aluminum like MacBook Pros, but described as "considerably slimmer" than current MacBooks with a screen that "reaches much closer to the edges".

Speculation has put a possible launch for the new range to take place at Macworld, Apple's big press event held in January, something that got more credible today.

Well-known Apple watcher, Piper Jaffrey’s Gene Munster, says he’s 75% certain that an ultralight MacBook "or possibly an entirely new product" will be announced then.

Apparently the recently released 64 gigabyte solid-state drive with NAND flash memory that Samsung released last week makes him so certain.

"We believe NAND Flash drive sizes have now reached capacities that Apple would consider large enough to include in a new MacBook model", Munster stated.

Still only rumours and speculation folks, and at this stage the ultra-portable is going to be fighting for space on the stage with the also rumoured iTablet, depending on which whispers you believe ... but we'll keep you informed.