StumbleUpon Explore Box

StumbleUpon (SU), a site that millions use to discover web content has just launched Explore Box, a new feature that lets users discover web sites in a more focused, and arguably, efficient, way. Previously, StumbleUpon did let users discover sites based on a limited list of categories. Now, StumbleUpon has increased the number of categories by a thousand-fold. Users can enter topics of interest in the Explore Box to define a topic of discovery. This allows a much more focused. For example, one can type Windows Phone 7 SDK, and discover relevant sites on this topic. This example is interesting because it also shows that you can’t stumble forever on random sites, as only sites that SU considers to be relevant are featured.

Stumble Upon’s Explore Box is currently in beta, and the company will refine it with the data gathered from user input. Have you tried SU before? How do you discover websites?