Skype will today announce the launch of full versions for Mac OS X and Linux, which include “the extensive functionality available in Skype for Windows 1.0 such as: free Skype to Skype calling and conference calling for up to 5 participants, cross-platform communications, rich presence and personalization features, and the pre-pay SkypeOut service – allowing users to call any landline or mobile worldwide for the price of a local call.”