Skype released four updates today. Skype 5.4 Beta for Mac and Skype 5.7 Beta for Windows are available for the desktop side of the world. Both updates feature Facebook-to-Facebook calls from within Skype. This requires connecting a Skype and Facebook account. Doing this lets you see when your Facebook friends are online from the Skype Mac or Windows clients.
Bring Your Social Network To Life (Skype – The Big Blog)
The Skype 3.5 updates for the iPhone and iPad are less ambitious. Skype notes improved stability for use on iOS 5 and various unnamed bug fixes. Note that Skype provides separate releases for the iPhone/iPod touch and the iPad.
Skype 3.5 for iPhone and iPad Update (Skype Garage)
Find the various Skype releases I mentioned above linked below: