Re-presentation and re-interpretation are the two maxillae of our anthropophagic era. Some companies are playing this ironic game to a fuller extend than others and the genetics of design are being explored and distorted by those Indiana Jones of aesthetics.
Apple is pulling a noticeable design trick by presenting, in total confidence, what they've been fighting in the past three years. After a long, colorful journey the company is going back to, or rather re-presenting, the white computer. No shame, just like when presenting the indeed very beautiful Apple Pro Mouse as if optical tracking mechanism was an Apple invention.
Of course "snow" is not exactly "white." It is a frozen (cool?) and potentially liquid white iMac, pushed forward as a teaser to announce and become the hardware complement of the "aqua" interface of MacOS X.
This non-color (or all-color depending on your perspective) is a response to the colorful machines that the company has presented in the recent past and that it's now notorious for. Apple recontextualizes white and makes it interesting again just because it is presented after an orgy of colors. It re-becomes the new frontier, what it always was but what users stopped seeing because of its deadly omnipresence.
The menacing black Mac cannot be very far behind.