This is a new version of the FreeSurround stereo upmixer (0.8); it was greatly expanded since the last release, and is in beta for now. The discussion takes places in this thread (http://www.hydrogenaudio.org/forums/index.php?showtopic=52235).
Note: From now on, you can always find the most recent version of the plugin attached to the first post (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=52235&view=findpost&p=467533) in the discussion thread.
Correction: had the wrong default value for Focus (should have been 0); upped version number to 0.8.1.