We have just updated our site (Aug 14 2011). We really liked our old site (below) but the two main reasons that made us take action were:
More people are viewing our site through mobile devices. Our new site is Responsive: You should see the layout adjust itself to fit the new width of the browser, even if you make the page as skinny as the resolution of a mobile phone. To see it in action, open this post on a desktop browser and slowly make the browser thinner and wider.
I like the old black background but have always thought that a white background looks more “friendly” and seeing as we are selling software on the site as well as our other activitys we have made the change