CSS NS WD

I am curious about the status of the CSS Namespaces WD
(http://www.w3.org/TR/css3-namespace/).

It is very neat that Mozilla 0.8 styles this:

ns-css.xml:
===========
<?xml-stylesheet href="ns-css.css" rel="stylesheet" type="text/css"?>
<test>
  <a xmlns="http://www.dog">Red</a>
  <a xmlns="http://www.cat">Blue</a>
</test>

with this:

ns-css.css:
===========
@namespace a url(http://www.dog);
@namespace b url(http://www.cat);

test { background: green }
a|a { color: red }
b|a { color: blue }

according to the WD and produces the expected result.

Is this something we can rely on becoming a Recommendation?

 Steve