Python 3.0 nonlocal statement

[Casey]

In PEP 3104 the nonlocal statement was proposed and accepted for
implementation in Python 3.0 for access to names in outer scopes.  The
proposed syntax included an optional assignment or augmented
assignment to the outer name, such as:

nonlocal x += 1

This syntax doesn't appear to be supported in the 3.0 implementation.
My question is: was this intentional or was it missed in the initial
release?  If it was intentional, is there any plan to support it in a
later 3.x release?  I realize it is a very small convenience feature
but I have already come across a couple of cases where I use nested
functions where it does make the code seem a little cleaner.

Regards, Casey