tedster - 7:35 pm on May 22, 2010 (gmt 0)

Yes, this is indeed a wake-up, isn't it? I just started thinking about everything that could combine to create a unique fingerprint - for example, how about the specific VERSION of every installed plug-in?

With regard to your title question, I do see the same results, even from from various computers, if the browser is logged in to any Google account and search history is also turned off for that particular Google account. I've tested this with a few other people's computers as well as my own. And no, that's not rigorous proof, but it's some good evidence.