Among the more noteworthy changes is a new screenshot feature that lets players take screenshots and upload them (automatically or manually) to the Steam cloud. You can take screenshots by pressing F12 in any DirectX 9 game or newer -- including non-Valve titles -- but DirectX 8 and earlier aren't supported yet. Pictures can be managed from the Steam community site and if there's something particularly awesome, you can share it through your Steam profile.
In our experience, the quality of Steam's voice communication has always been lackluster. Valve is attempting to address this by increasing microphone voice input from 11KHz to 16KHz and voice output has been boosted from 8KHz to 16KHz. The remaining changes:
* Moved game invites from friends outside of the chat stream, into their own panel in the chat dialog
* [Mac OSX] Fixed a problem where attempting to resume a paused/interrupted download could always report 'server unavailable'
* Fixed games not launching automatically after resolving a cloud conflict
* Fixed download rate sometimes erroneously reporting very high speeds
* Possible fix to crash on startup or when viewing Games page
* Added password strength meter when you change your password
* Added UI prompting you to choose a new password if you've had support change your password