Not sure if others have noted the new open source census effort, which aims to measure open source software use both locally (via use of a new OSS Discovery tool) and globally through the aggregation of local discovery data.
http://www.osscensus.org/
http://ossdiscovery.opensource.collab.net/
We've long been maintaining that open source technologies are in wide—and often unrecognized—use in many organizations. Now we have an initiative and a tool to help demonstrate that claim with real numbers. I've blogged about the census/discovery where I suggest that institutions might incorporate OSS Discovery into a standard practice for analyzing institutional readiness for OSS:
http://xolotl.org/node/50
How might the Drupal community support the census in order to augment our understanding of Drupal's global usage?
I a submitted a request for the OSS Discovery tool to establish a Drupal fingerprint and it has already been done by the OSS Discovery team:
http://ossdiscovery.opensource.collab.net/issues/show_bug.cgi?id=13