The co-author of Lucene in Action, this presentation could probably have been termed a keynote. Erik is working with Lucene and Solr in quite a few projects and some of the displays are fairly interesting. Most of these projects are listed under patacriticism.org though there is another called Juxta which also used Lucene though mostly for data analysis.
There was more information in the presentation but I found it hard to summarize some of it. I really found the Collex interface concept to be very interesting. Everything is a contraint or limit and you can easily add or invert the contraint. It’s also easy to add things to a personal collection and parts of the personal collection then become facets/contraints themselves. He’s really using all of the metadata (archive and user) to it’s full extent. He also has more plans including “exhibits” where people can “curate collections”. These collections themselves can then become objects in the index and so on. This project will be something to watch.