Document serializing querysets

docs/api-guide/serializers.md

@@ -80,6 +80,15 @@ By default, serializers must be passed values for all required fields or they wi
 
     serializer = CommentSerializer(comment, data={'content': u'foo bar'}, partial=True)  # Update `instance` with partial data
 
+## Serializing querysets
+
+To serialize a queryset instead of an object instance, you should pass the `many=True` flag when instantiating the serializer.
+
+    queryset = Comment.objects.all()
+    serializer = CommentSerializer(queryset, many=True)
+    serializer.data
+    # [{'email': u'leila@example.com', 'content': u'foo bar', 'created': datetime.datetime(2012, 8, 22, 16, 20, 9, 822774)}, {'email': u'jamie@example.com', 'content': u'baz', 'created': datetime.datetime(2013, 1, 12, 16, 12, 45, 104445)}]
+
 ## Validation
 
 When deserializing data, you always need to call `is_valid()` before attempting to access the deserialized object.  If any validation errors occur, the `.errors` and `.non_field_errors` properties will contain the resulting error messages.