The Skype team announced today that the old Windows and Mac versions of the Skype client will be retired (unavailable) in the next few months, specifically referring to the Windows desktop version of the Skype client version number 6.13 and below, and the Mac version of the Skype client version number 6.14 and below, this includes the old desktop Skype client on Win7, Win8.1 and Mac systems.

Skype encourages users to upgrade to the latest Skype version to enjoy some of the latest functional improvements: offline messaging, cross-platform chat history synchronization, and cross-platform message reading status synchronization.

According to previous announcements by Microsoft Skype, they are already testing a new interface for the Windows desktop version of the Skype client, which will be more "modern and clean." The new interface for the Mac version of Skype will also arrive soon, but it has never shared more information beyond text.