It's worth noting that, yes, Yahoo gets that one right - but it gets other things wrong. And both Google and MSN get that one right.
Moral of the story: Precise calculations on a computer are surprisingly difficult, and "quick fixes" generally cause unexpected problems. There is a right way of doing this - but so far, none of the big search engines have implemented it.
(Actually, looking over it again, it might not be thanks to that post. It's shown up on Digg around the same time. Actually, it's showing up all over the place. Damn viral memes. I wish people would stop sending me bug reports. I dunno, maybe I should fix the fucker, but it's annoyingly difficult.)