The AC/DC motto could gain more popularity in an energy-conscious world. Please have a look at this attempt to render a low power Google. The creators of Blackle know fairly well that the energy demand of an LCD screen is quite the same whatever it displays but building consciousness on a brand like Google is a certainly a clever move.
As a matter of fact, black IS gaining momentum as the color of choice for our screens. Let’s be more precise : GLOSSY black is coming out. From the interfaces of Apple software to the frames of our screens, black comes back to enhance the brillance and constrast of our information, might it be the elaborated pictures of CD covers of even… plain text. I use WriteRoom as my word processor because it is able to turn the display of my beloved MacBook into a soviet-era terminal with green type and nothing else. Why? Because it is way more comfortable to the eye and the brain that is attached behind. Light is used for information, not to complement a surrounding blank.
Apple and Xerox introduced the white background and the mouse at the same time when they released the first generaztion of Lisa computers and DocuCenters. It was a breaktrough because it enhanced the visual quality of the text by generating a « white pressure » over it that exagerated the definition of the screens and allowed to see thin lines. Microsoft copied that and it became a de facto standard for all windows and Pages themed interfaces. Now that 3D chips perform their tricks to take charge of the information, white backgrounds are no longer the obvious choice.