Cumulative release notes for 3.6 to now, language is Skype's:

New features in 3.6:

• Calling support for MySpace with Skype users
• Display MySpace avatar in Skype
• Linking MySpace profile in Skype
• High Quality Video calls
• User notification if he has old Logitech driver version

changes:

• Computers with Dual Core CPU's will send 640x480 by default on video call with High Quality Video certified cameras
• Extras Manager updated to version 1.5.0.32
• Skype Internet Explorer plugin updated to 2.2.0.145
• Improved audio quality on low speed internet connections
• Improved presence [editor: ???]
• More stable video calls between fast and slow internet connection users
• Relayed file transfer speed improved to up to 70 kbytes/sec

For programmers, API changes:

• Check and set Skype window status
• Notification for changing state of the Skype main window (minimized, maximized, normal, hidden)
• Notification for opening and closing Skype Chat windows

Updated language files:

• Arabic, Bulgarian, Czech, Danish, German, Estonian, Greek, French, Italian, Japanese, Hungarian, Latvian, Lithuanian, Norwegian, Dutch, Polish, Portuguese-Portugal, Portuguese-Brazil, Finnish, Swedish, Russian, Romanian, Turkish