Web Sites with Black Backgrounds - A New Trend?

Recently, we came across a posting about using a black background on your Web site. In this year of Live Earth and green thinking, black backgrounds are supposed to conserve energy.

A lot of this started as a criticism to Google because their Web site is all white. White backgrounds use about 15 watts more energy to load a page than black backgrounds.
One media company has even gone so far as to create a special site, called Blackle, that uses Google search capabilities from an all black page.Also, a few large companies seem to have jumped on the black background bandwagon: ASTD and Business Objects, makers of Crystal Reports.

Well, as you can see from our site, we're definitely not in compliance with the trend. Saving energy makes sense. But readability is a concern. Any thoughts on this trend - yea or nay?