Apple has begun sending emails about a new hard drive recall, called the iMac 1TB Seagate Hard Drive Replacement Program



From MacRumors:

Apple has determined that a very small number of Seagate 1TB hard drives used in 21.5-inch and 27-inch iMac systems, may fail under certain conditions. These systems were sold between May 2011 and July 2011.

Apple or an Apple Authorized Service Provider (AASP) will replace affected hard drives free of charge.

  Apple Recalls Some iMac Seagate 1TB Hard Drives