If you use Microsoft Lync 2010 or 2013 and PIC federation to communicate with AOL networks or Yahoo! (I have still yet to see a Yahoo! federation), please keep in mind that on June 30th, 2014, this service will no longer be available. For more detail, please see the following: http://technet.microsoft.com/en-us/library/dn458579.aspx in the “Yahoo! and AOL Instant Messenger” section.
What you should know is that AOL federation is now supported directly for Lync deployments. Please see AOL’s site for more provisioning information: https://aimenterprise.aol.com/microsoft/