edit: I'm not even sure if it's only search engines that are being analysed by Bing or all pages, but it's possible that it is just SEs - they could be capturing query terms distinctly.
Also, why did the experiment succeed for only 6 or 7 of the 100 terms that they tried? There's more than what meets the eye here, regardless of the hype and everyone jumping on the bandwagon.
edit: I'm not even sure if it's only search engines that are being analysed by Bing or all pages, but it's possible that it is just SEs - they could be capturing query terms distinctly.