Thomas Goetz’s Wired article Open Source Everywhere unsuprisingly positions open source as efficient business practice first, an alternative to the more repressive manifestations of IP second. But I did like this pithy description of how open source might be measured:

think of it as a spectrum or – better still – a rising diagonal line on a graph, where openness lies on one axis and collaboration on the other. The higher an effort registers both concepts, the more fully it can be considered open source.

Despite the hideousness of suggesting that oil companies can benefit from open source science, the article is extended and actually includes some interesting examples of open source creativity and information, including open source film, OpSound, and of course the Wikipedia.