If you already have emesene installed and don't want to wait until a package for your OS is available (or maybe YOU are the packager!), just grab the archive here [zipball|tarball] extract and run the emesene script.
There have been many changes and lots of bugfixing but they're just too much and quite boring to list all of them here so..
Brief changelog since 2.11.11:
- Revamped contact list search
- Fixed conversations with Yahoo users
- Fixed some problems with messages not being received/sent
- Implemented plugin updates
- Updated default Adium conversation theme
- Lots of bugfixing both in library and gui
- Tighter Facebook integration in Facebook session
- Updated translations
- the last said plugin breaks the conversation, just don't use it for now
- adium output is broken in windows 7 because no dev has this os
Thanks to everyone involved in this new-year release and happy 2012 from the emesene team.