Not really that impressed
I use IE8, and make no particular attempt to hide or clean my browsing history - granted, it contains a few references to Redtube, but as a 30 year old bloke, I'm not ashamed to admit to looking at the odd bit of porn.
This site identified a less-than-impressive two sites I'd visited - one was theirs (well, duh), and the other was badscience.net.
So where are all the others? I've visited hundreds since I last cleaned the history...