Apologies for the cross-post. 

Blacklight 4.0.0 was just released yesterday evening.  One of the most notable changes in this release is a switch to using Twitter Bootstrap for our UI component.  We have taken a fairly generic approach which will allow implementers to take full advantage of the features Bootstrap provides (including drop-in Bootswatch themes).  You can see the new Bootstrap UI for Blacklight at our demo site ( http://demo.projectblacklight.org/ ).

Other notable changes are:
- Removing dependency on RSolr::Ext which allows us to leverage new solr features as the come out.  One such feature (Pivot Facets) is supported in this release.
- Updated blacklight-jetty submodule to solr 4.0. (note that we expect to remain compatible with 3.x and 1.4 moving forward)
- Drop support for ruby 1.8.

In addition to the core release we have upgraded most (if not all) of the plugins under the projectblacklight Github organization to work with the 4.0.0 release.

For more information about what this release contains as well as an upgrade guide please see our wiki:
https://github.com/projectblacklight/blacklight/wiki/Blacklight-4.0-release-notes-and-upgrade-guide

Very special thanks to the developers in the Blacklight community that did the heavy lifting on this release: 
Chris Beer (Stanford)
Simon Lamb (Hull)
James Stuart (Columbia)
Justin Coyne (MediaShelf)

As always, please feel free to contact us via email ( [log in to unmask] ) or on IRC ( http://webchat.freenode.net/?channels=blacklight )

- Jessie Keck
Software Developer
Stanford University