start talking about polymer.dart

src/site/articles/web-ui/index.markdown

Index: src/site/articles/web-ui/index.markdown
diff --git a/src/site/articles/web-ui/index.markdown b/src/site/articles/web-ui/index.markdown
index 767525b8ea205d5d97ae6914d88acc5f593c55ce..74182471d28e879405628550ae1cc5ef78480bf6 100644
--- a/src/site/articles/web-ui/index.markdown
+++ b/src/site/articles/web-ui/index.markdown
@@ -44,8 +44,26 @@ that will contain the running version of the code sample.
 {% iframeprefix example/ %}
 {% endcodesampleSetup %}
 
+<div class="hero-unit">
+      <h1> Introducing Polymer.dart </h1>
+      <p markdown="1">
+        [Polymer.dart](/polymer-dart/), the next evolution of Web UI, has
+        better debugging,
+        faster development, and closer spec alignment.
+        Upgrade to Polymer.dart today!

[mem, 2013/09/04 17:39:55]

I'm surprised we're encouraging people to upgrade now. That wasn't the
impression I had yesterday.

[sethladd, 2013/09/04 21:11:02]

I'll take it out.

+      </p>
+</div>
+
 # {{ page.title }}
 
+<aside class="alert alert-danger" markdown="1">
+<strong>Web UI is now Polymer.dart.</strong>
+Web UI has evolved to
+[Polymer.dart](/polymer-dart/), with many fixes and improvements.

[mem, 2013/09/04 17:39:55]

with -> which provides

[sethladd, 2013/09/04 21:11:02]

Done.

+We encourage Web UI users to upgrade to Polymer.dart.
+The contents of this page apply only to Web UI, which is now deprecated.

[mem, 2013/09/04 17:39:55]

The contents of this page apply only -> The information on this page applies
only ...

[sethladd, 2013/09/04 21:11:02]

Done.

+</aside>
+
 _Written by Sigmund Cherem<br />
 October 2012 (Updated February 2013)_