If you are a mage or druid (capable of removing Archimonde's Grip of the Legion in the Battle for Mount Hyjal), you will see a large message indicating the name of the person who is cursed and, if in range, a message indicating that you are able to remove that curse.
If you are not capable of removing said curse, you will only receive a notification if you are the one who has been cursed.
When the curse is removed, all raid members running this addon will be notified of its removal.
Range notification for other classes
Live range updates until the curse has been removed
Ability to enable/disable curse-removal notification