removed observer pattern, in favour of mediator

src/Symfony/Component/EventDispatcher/GenericEvent.php

@@ -21,7 +21,7 @@ namespace Symfony\Component\EventDispatcher;
 class GenericEvent extends Event implements \ArrayAccess, \IteratorAggregate
 {
     /**
-     * Observer pattern subject.
+     * Event subject.
      *
      * @var mixed usually object or callable
      */

src/Symfony/Component/EventDispatcher/README.md

@@ -1,8 +1,9 @@
 EventDispatcher Component
 =========================
 
-EventDispatcher implements a lightweight version of the Observer design
-pattern.
+The Symfony2 Event Dispatcher component implements the Mediator pattern
+in a simple and effective way to make all these things possible and
+to make your projects truly extensible.
 
     use Symfony\Component\EventDispatcher\EventDispatcher;
     use Symfony\Component\EventDispatcher\Event;