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lucy24 - 2:54 am on Sep 29, 2012 (gmt 0)
How long should I wait before I disallow the page in robots.txt?
Forever. The moment you disallow the page, search engines can no longer see the "noindex" directive, so you're right back where you started.
You might think that indexing a page when you haven't seen a single word of its content is pretty pointless-- but what the search engine can see is the linking text from anyone in the world that links to the page. And so far there's no such thing as an inverse nofollow. ("If a link leads to this page, pretend you never saw it.") At least not in g###.