Skype has pushed out a new version for PC and Mac, v.6, which introduces Facebook Chat integration as well as Retina Display support for the OS X client. The updated VoIP and video calling app can now pull in Windows Live Messenger, Outlook.com, and Hotmail contacts, thanks to further Microsoft integration between its products, and in fact you no longer need a separate Skype account at all.
Instead, you can use your existing Facebook or Microsoft credentials to log in, and if you choose the latter then the various chat services Microsoft offers will instantly be supported too. Microsoft had already been talking up its Skype for Windows 8 app, completely redesigned to suit the Metro-style UI.
In the pipeline, meanwhile, is the ability to break out chat conversations into different windows so as to more easily monitor them on the Mac app; that's already enabled in the PC version. There'll also be the ability to make audio/video calls directly to Windows Live Messenger users from the Skype app, which Microsoft says is due in the "coming weeks."
Skype is a free download, though there are premium services which you can pay for. Those include unlimited voice calls to landlines, group video chats for up to ten participants, and instant live-chat support from Skype itself.