Why Bing trumps Google when searching for nude celebs (NSFW)

I admit to anyone who asks that I have a mild obsession with celebrity nudity. I also have a major aversion to paying for it. So part of my daily Web routine involves regular visit to some free celeb nude sites like Egotastic, Nudography, and Babes of Babylon. The pics are free, at least when they first go up, and I collect them like found coins, stuffing them into a folder on my computer in hopes they'll some day pay future dividends (if you know what I mean). But what about the stuff I miss? What about the stuff I've lost? Just the other day I couldn't find my pic of NCIS supporting actress and resident goth chic, Pauley Perrette. I knew she'd posed topless and the pic was on some site somewhere, but Google totally let me down. So I did something I've never, ever done before: I searched using Bing!