September’s beta is October’s whole number release and, as noted at the time, much of what’s new in Skype for Mac is Microsoft integration. Yes, the slow march to oblivion is formally under way — step inside for the details.

Last month, the Fairer Platform noted the release of Skype 5.11 beta, which was all about making the once proud and industry leading VOIP and video chat a lot more Microsofty.

Today, Skype 6 (blog) has arrived and offers the following “new” features:

• Microsoft and Facebook Account Integration
• IM friends on Microsoft Messenger
• Open Chats in Multiple Windows
• Retina Display Support
• Automatic background app updates
• Calling with Messenger friends is “coming soon”

I was able to login with my legacy Skype account credentials, but imagine that Microsoft and Facebook account login will be the only options some time in the not too distant future. Fundamentally, the services Skype for Mac provides are features rather than a standalone business model.

Download Skype for Mac v6 here — requires a 1GHz or faster Intel Mac running OS X v10.5.8 with 100MB of free space.

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