But last week, it seems the feature went missing.
If you try to access it at http://wap.google.com/gwt/n it 404s.
Google's John Mueller posted in a Google Webmaster Help thread this morning saying "Thanks for posting -- I'll double-check with the team!"
So it does seem to be gone. Truth is, I am not sure how much use it got.
This is what it looked like in the past:
Forum discussion at Google Webmaster Help.