The Open Knowledge Foundation has released CKAN (Comprehensive Knowledge Archive Network) version 1.0.
Here's an excerpt from the announcement:
As well as being used to power http://ckan.net and http://data.gov.uk CKAN is now helping run 7 data catalogues around the world including ones in Canada (http://datadotgc.ca / http://ca.ckan.net), Germany (http://de.ckan.net/) and Norway (http://no.ckan.net).
CKAN.net has also continued to grow steadily and now has over 940 registered packages:
Here's a description of CKAN from the project page:
CKAN is a registry or catalogue system for datasets or other "knowledge" resources. CKAN aims to make it easy to find, share and reuse open content and data, especially in ways that are machine automatable.