You can still see inbound video call while you are in multi-tasking. With call control bar, you can mute, or hang up call easily without switching back to Skype.
Group Screen Sharing
Users with Skype Premium subscription can enable screen sharing during a group video call.
You can find your most active conversations more easily under Recents in the sidebar by moving less active ones to History section.
Support for Mac's built-in HD and Logitech's B910 HD cameras
Both incoming and outgoing HD are supported for those two cameras.
In addition to new features and enhancements, Skype fixed bugs reported by users.
The new version of Skype for Mac can be downloaded here