Update: a new release candidate for darktable 2.0 has been issued. See this post for installation instructions.
The darktable team have released a new version: 2.0.
This is a big update from the current version, 1.6. A full list of features, and download instructions can be found here.
Bear in mind the following warning:
When updating from the currently stable 1.6.x series, please bear in mind that your edits will be preserved during this process, but it will not be possible to downgrade from 2.0 to 1.6.x any more. Be careful if you need darktable for production work!