User:AntHolnes told me about a curious thing. If you lot out of wikipedia, clear all of your browser cache, and go to the history of [[Sarah Lacy]], and diff the earliest two versions, the diff will claim that the version on the right is the current one, even though it isn't.
AntHolnes even made a cool screen recording of it: http://i246.photobucket.com/albums/gg92/ahwpsl/wpsl.gif
I have confirmed the effect in a "clean" Opera as well.
I know we have some weirdness with revision numbers, but these seem to be all ascending. Also, the URL of the diff clearly states the old revision number, not the current one.
Or maybe it's an old squid cache?
Magnus