I am so happy to inform you that Communicator for MAC 2011 includes now the awesome "desktop sharing feature"! this is a really interesting update to the Communicator for MAC 2011 in addition to all the basic lync client features.
The new feature has been introduced as part of the Communicator for MAC 2011 13.1 "KB2476505" update.
As a reminder and for those who doesn't know that Communicator for MAC is the Lync 2010 Client that runs on MAC OS. and this client is part of the Microsoft office for MAC 2011 suite.
as many of you are wondering where the Lync trial download is, yes it has been moved from some reason from it's original location http://lync.microsoft.com/en-us/TryIt/Pages/try-it.aspx
but you can still get it from Microsoft Technet evaluation Center here
kindly note that you have to be logged in to Microsoft Technet website