Added notes on OpenAPI changes for 3.11.

docs/community/3.11-announcement.md

@@ -28,7 +28,33 @@ This release will be the last to support Python 3.5 or Django 1.11.
 
 ## OpenAPI Schema Generation Improvements
 
-...
+The OpenAPI schema generation continues to mature. Some highlights in 3.11
+include:
+
+* Automatic mapping of Django REST Framework renderers and parsers into OpenAPI
+  request and response media-types.
+* Improved mapping JSON schema mapping types, for example in HStoreFields, and
+  with large integer values.
+* Porting of the old CoreAPI parsing of docstrings to form OpenAPI operation
+  descriptions.
+
+    Here with an example view class:
+
+        class DocStringExampleListView(APIView):
+        """
+        get: A description of my GET operation.
+        post: A description of my POST operation.
+        """
+        permission_classes = [permissions.IsAuthenticatedOrReadOnly]
+
+        def get(self, *args, **kwargs):
+            pass
+
+        def post(self, request, *args, **kwargs):
+            pass
+
+    Operation descriptions for the `get` and `post` methods will be extracted
+    from the class docstring.
 
 ## Validator / Default Context