Apple has started a replacement program for a “very small number” of Seagate 1 TB hard drives that may fail in certain conditions. These drives came in 21.5-inch and 27-inch iMacs sold between May 2011 and July 2011. Although Apple is contacting iMac purchasers who provided a valid email address during the product registration process, you can also enter your iMac’s serial number on this page to see if it’s included in the replacement program. As always, back up your data regularly, and be certain to run a backup right before you take your Mac in for the replacement so you can restore onto the new drive. follow link
Two Shortcuts for App Exposé
If you want to see all the windows for a particular app via App Exposé, there are two hidden shortcuts. For either, start by pressing Command-Tab to bring up the app switcher. Then, while still holding down the Command key, press either the 1 key or the up arrow. That puts you into App Expose mode, with all of an app's windows showing, and recent documents in a row across the bottom of the screen. Let up on the Command key, and then you can press Tab to cycle through all the running apps.
Apple Replacing Some 1 TB iMac Hard Drives