One problem with Cuil is that it looks terrible. Supposedly, we can save a lot of energy if Google goes black. But white screens look better. I remember there was the Netscape portal (which used to be a white backgrd, and visually it was contrastful. Now, it's evergreen green: more homely.
Perhaps Google can go to a night sky (much like the original Netscape browser w. the desert vista). The stars would go a long way to making Cuil actually "cool"; at least in visual appearance.