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(or something like that).
It was just below the sponsored links and above the #1 position, so in some real prime real estate.
Not sure if I saw this because I was using IE when I normally don't. I don't expect it means much, but it was a bit disconcerting for a second to see non-serp info in a spot I expect to see serp info.
Yet another reason to cut extra parameters out of Google URLs when you paste them into a forum or blog, or save them as a bookmark; however I do wonder if the Google techs were clever enough to then hide the message if the referrer wasn't a place where a Google Search Button could actually exist. I haven't checked.