Apple to End Support for AIM iChat Logins on Older Versions of OS X Starting June 30 - Mac Rumors
Apple has announced in a recent support note (via ZDNet) that it will end AIM iChat login support for users running versions of OS X below 10.7.2 Lion on June 30, 2014.
The change will affect those who use their mac.com and me.com addresses as AIM IDs to log into iChat on older systems, as users running compatible versions of OS X Snow Leopard and OS X Lion can upgrade to OS X Mavericks for free.
Meanwhile, users running OS X Leopard are directed to purchase and upgrade to Snow Leopard and then install OS X Mavericks for free. If a user cannot upgrade to a newer version of OS X, then the creation of a new AIM ID on AOL's website will be required along with the need to repopulate a new contacts list.
iChat was discontinued in favor of Messages, which has been the default instant messaging application on the Mac since its first appearance in OS X 10.8 Mountain Lion. According to the latest data from Net Applications, Apple’s newest operating system, OS X Mavericks, holds a 51% share on all Macs, while the share of systems running older versions of OS X affected by this latest change is 19%.