Well it started as a better UI than Google's (I said too much here), so I started designing the UI with search as a focus. Than later it evolved.<p>As for the usable thing, most of UIs I design are usable from the start, in the sense that they don't suffer the designer syndrome.<p>If you want to see a scifi that suffers usability<p>Mozilla's Aurora Concept <a href="http://www.adaptivepath.com/aurora/" rel="nofollow">http://www.adaptivepath.com/aurora/</a>