Add more prominent warning about incompatible changes in 2.0

diff --git a/website/templates/index.html b/website/templates/index.html
index aad0915209e4937fdbe23d9135f30a8b1e0442b5..0a194fcfe896c44404468127aa06d7077810eb8a 100644 (file)
--- a/website/templates/index.html
+++ b/website/templates/index.html
@@ -4,6 +4,14 @@
   <p><a href="http://www.tornadoweb.org/">Tornado</a> is an open source version of the scalable, non-blocking web server and tools that power <a href="http://friendfeed.com/">FriendFeed</a>. The FriendFeed application is written using a web framework that looks a bit like <a href="http://webpy.org/">web.py</a> or <a href="http://code.google.com/appengine/docs/python/tools/webapp/">Google's webapp</a>, but with additional tools and optimizations to take advantage of the underlying non-blocking infrastructure.</p>
   <p>The framework is distinct from most mainstream web server frameworks (and certainly most Python frameworks) because it is non-blocking and reasonably fast. Because it is non-blocking and uses <a href="http://www.kernel.org/doc/man-pages/online/pages/man4/epoll.4.html"><code>epoll</code></a> or <code>kqueue</code>, it can handle thousands of simultaneous standing connections, which means it is ideal for real-time web services. We built the web server specifically to handle FriendFeed's real-time features &mdash; every active user of FriendFeed maintains an open connection to the FriendFeed servers. (For more information on scaling servers to support thousands of clients, see The <a href="http://www.kegel.com/c10k.html">C10K problem</a>.)</p>
 
+  <h2>Upgrading from Tornado 1.x</h2>
+
+  <p>Tornado 2.0 introduces several potentially backwards-incompatible changes,
+    including in particular automatic escaping of template output.  Users
+    who are upgrading from Tornado 1.x should see the 
+    <a href="/documentation/releases/v2.0.0.html">release notes</a> for
+    information about backwards compatibility.</p>
+
   <h2>Quick links</h2>
 
   <ul>