diff --git a/docs/releases/v3.0.0.rst b/docs/releases/v3.0.0.rst
index ac3cf0d8..e618641f 100644
--- a/docs/releases/v3.0.0.rst
+++ b/docs/releases/v3.0.0.rst
@@ -50,6 +50,8 @@ Backwards-incompatible changes
 * ``tornado.netutil.TCPServer`` has moved to its own module,
   `tornado.tcpserver`.
 * The Tornado test suite now requires ``unittest2`` when run on Python 2.6.
+* `tornado.options.options` is no longer a subclass of `dict`; attribute-style
+  access is now required.
 
 
 Detailed changes by module