It was less than two weeks ago that PulseAudio 0.9.20 was released
as a bug-fix release, but PulseAudio 0.9.21 was pushed out today to offer up more bug-fixes. Besides carrying eight bug fixes to this software package that is loved by some and hated by others, PulseAudio 0.9.21 also integrates the device-manager module.
PulseAudio's device-manager module is used to keep track of the names and descriptions of any and all audio devices. This module then also provides a protocol extension for other programs to query this information. At this time, device-manager will largely be used in integrating support for KDE Phonon. The device-manager module is considered experimental at this time along with its API.
The official change-log for PulseAudio 0.9.21 is available at PulseAudio.org