Microsoft has release an official annoucement that PIC would be retiring from the licensing list. Yahoo! Messenger would likely no longer be available (to be confirmed within the 1st Half of 2013).

This retirement doesn’t impact AOL and Live Messenger and XMPP gateway Messengers and another provider that everyone has been waiting for – SKYPE would be added into the federation list! Wooohooo! These Public IM connectivity is available within the Lync Standard CAL.

Email Source is from Microsoft APOC:

SUMMARY
As of the September Price List, the Microsoft Lync Public IM Connectivity User Subscription License (PIC USL) will no longer be available for purchase for new or renewing agreements.
DETAILS / PURPOSE
As of the September Price List, the Microsoft Lync Public IM Connectivity User Subscription License (“PIC USL”) will no longer be available for purchase for new or renewing agreements. Customers with active licenses will be able to continue to federate with Yahoo! Messenger until the service shut down date (exact date TBD, but no sooner than June 2013).The PIC USL is a per-user per-month subscription license that is required for Lync Server or Office Communications Server to federate with Yahoo! Messenger. Microsoft’s ability to provide this service has been contingent upon support from Yahoo!, the underlying agreement for which is winding down.

Along with the Yahoo! federation capabilities, the PIC USL license is being retired. Customers with active PIC subscriptions will be able to continue to federate with Yahoo! until the service shut down date (date TBD, but no sooner than June 2013). More than ever, Lync is a powerful tool for connecting across organizations and with individuals around the world. Federation with AOL and Windows Live Messenger requires no additional user/device licenses beyond the Lync Standard CAL. Next year, Skype federation will be added to this list, enabling Lync users to reach hundreds of millions of people with IM and voice. Moreover, XMPP federation is available via the deployment of a Microsoft-developed gateway to communicate with XMPP-base IM and presence providers such as Google Talk.

Additional communications will be sent later in FY13 to confirm the process for compensating customers whose subscriptions extend beyond the date when the service will shut down (exact date TBD, but no sooner than June 2013).

Additional information and updates can be viewed at the following sites: 

PROGRAMS IMPACTED
Campus, Enterprise, Open Value, Select Plus, School