update release notes (#137)

Author: rachel-mack

source/reference/release-notes.txt

@@ -149,15 +149,15 @@ Removal of Deprecated Class ``Mongoid::Errors::InvalidStorageParent``
 The deprecated class ``{+odm+}::Errors::InvalidStorageParent`` has been
 removed.
 
-``around_*`` Callbacks for Embedded Documents are Ignored
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+``around_*`` Callbacks for Embedded Documents are Ignored by Default
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 {+odm+} v8.x and older allow user to define ``around_*`` callbacks for embedded
-documents. Starting in v9.0, these callbacks are ignored and will not be executed.
-A warning will be printed to the console if such callbacks are defined.
+documents. Starting in v9.0, by default these callbacks are ignored and will
+not be executed. A warning will be printed to the console if such callbacks are defined.
 
 If you want to restore the old behavior, you can set
-``Mongoid.around_embedded_document_callbacks`` to true in your application.
+``Mongoid.around_callbacks_for_embeds`` to true in your application.
 
 .. note::