Today, this announcement came from Apple’s support site:
Apple has determined that a very small number of 3TB hard drives used in 27-inch iMac systems, may fail under certain conditions. These systems were sold between December 2012 and September 2013.
Apple or an Apple Authorized Service Provider (AASP) will replace affected hard drives free of charge.
Apple is contacting affected iMac owners who provided a valid email address during the product registration process to let them know about this program. If you have not been contacted, but think you have a 3TB hard drive, you can enter your serial number below to see if it’s part of this program.
How to check to see if your iMac qualifies for this replacement program: Head to this page on the Apple support site. You’ll need to have the serial number of your iMac handy. It may be found on your purchase receipt. If that’s not readily available, here’s a page on Apple’s site that describes several methods of finding it.
Replacement Process: Does your iMac qualify? Apple recommends replacing affected hard drives as soon as possible. As an Apple Premium Service Provider, Connecting Point is fully capable of taking care of this replacement, regardless of where you purchased your iMac. Contact Connecting Point SERVICE as soon as possible to facilitate your repair:
Back up everything on your iMac before you bring it in to us. This part is important. You’ll need to re-install your operating system, other applications, and any documents or data after your hard drive is replaced. If you would like Connecting Point SERVICE to take care of this for you, we’re more than happy to do so – but we’ll have to charge for that part of the repair.
Other details: If you believe you have paid for a repair or replacement due to this issue, contact Apple regarding a refund. This worldwide Apple program does not extend the standard warranty coverage of the iMac. The program covers affected iMac models until December 19, 2015 or three years from its original date of sale, whichever provides longer coverage for you.