Steve Tweeted https://twitter.com/SGgrc/status/297165652257554432:
GRC'S new UPnP Exposure Test is NOW ONLINE. Goto http://grc.com Choose "ShieldsUP!"... and you can't miss it.
http://grc.com is direct link, above is twitter shortened link to same url, ShieldsUP is large image with link on that page.
Easy & simple to do, not complicated to use, if you can click a mouse you can use it.
According to this Tweet from Steve, OpenWRT is vulnerable as well, https://twitter.com/SGgrc/status/297173997743902720:
UPnP: I'm checking returned data, but NO IP addresses. I've seen that a Roku is exposed, and so is OpenWRT (and lots of other stuff!)