* Authors of alternative `.IOLoop` implementations should see the changes
to `.IOLoop.add_handler` in this release.
+* `tornado.concurrent.Future` is no longer thread-safe; use
+ `concurrent.futures.Future` when thread-safety is needed.
+
+`tornado.concurrent`
+~~~~~~~~~~~~~~~~~~~~
+
+* `tornado.concurrent.Future` is now always thread-unsafe (previously
+ it would be thread-safe if the `concurrent.futures` package was available).
+ This improves performance and provides more consistent semantics.
+ The parts of Tornado that accept Futures will accept both Tornado's
+ thread-unsafe Futures and the thread-safe `concurrent.futures.Future`.
+* `tornado.concurrent.Future` now includes all the functionality
+ of the old ``TracebackFuture`` class. ``TracebackFuture`` is now
+ simply an alias for ``Future``.
+
+`tornado.gen`
+~~~~~~~~~~~~~
+
+* The internals of the `tornado.gen` module have been rewritten to
+ improve performance when using ``Futures``, at the expense of some
+ performance degradation for the older `.YieldPoint` interfaces.
+* Performance of coroutines has been improved.
+* Coroutines no longer generate ``StackContexts`` by default, but they
+ will be created on demand when needed.
`tornado.ioloop`
~~~~~~~~~~~~~~~~
in addition to raw file descriptors. Passing the objects is recommended
(when possible) to avoid a garbage-collection-related problem in unit tests.
+`tornado.iostream`
+~~~~~~~~~~~~~~~~~~
+
+* The ``callback`` argument to most `.IOStream` methods is now optional.
+ When called without a callback the method will return a `.Future`
+ for use with coroutines.
+
+`tornado.options`
+~~~~~~~~~~~~~~~~~
+
+* It is now possible to disable the default logging configuration
+ by setting ``options.logging`` to ``None`` instead of the string "none".
+
+`tornado.platform.asyncio`
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+* Now works on Python 2.6.
+
+`tornado.stack_context`
+~~~~~~~~~~~~~~~~~~~~~~~
+
+* The stack context system now has less performance overhead when no
+ stack contexts are active.
+
+`tornado.testing`
+~~~~~~~~~~~~~~~~~
+
+* `.AsyncTestCase` now attempts to detect test methods that are generators
+ but were not run with ``@gen_test`` or any similar decorator (this would
+ previously result in the test silently being skipped).
+* Better stack traces are now displayed when a test times out.
+
+`tornado.web`
+~~~~~~~~~~~~~
+
+* When gzip support is enabled, all ``text/*`` mime types will be compressed,
+ not just those on a whitelist.
+
`tornado.websocket`
~~~~~~~~~~~~~~~~~~~
+* `.WebSocketHandler.close` and `.WebSocketClientConnection.close` now
+ support ``code`` and ``reason`` arguments to send a status code and
+ message to the other side of the connection when closing. Both classes
+ also have ``close_code`` and ``close_reason`` attributes to receive these
+ values when the other side closes.
* The C speedup module now builds correctly with MSVC, and can support
messages larger than 2GB on 64-bit systems.