Documented Evented differences from Node.js events

src/event/Evented.js

@@ -36,7 +36,16 @@ var Trait   = require( 'easejs' ).Trait,
  * listeners.
  *
  * The API is motivated by (and is a replacement for) Node.js' event emitter
- * implementation, but is more robust.
+ * implementation, but is more robust. Note, however, that it differs
+ * significantly in a number of implementation details:
+ *
+ *   - All events must be pre-registered, and all listeners must hook a
+ *     registered event;
+ *   - The same listener cannot be attached to the same event multiple
+ *     times (will produce an exception);
+ *   - There is no special `error' event that will, if unhooked, trigger an
+ *     exception when emitted; and
+ *   - It is implemented as a trait.
  */
 module.exports = Trait( 'Evented',
 {