Neither the title nor the judging requirement statement include that, however.

I'd say that the text and title are subordinate to the judging criteria. Had the judging statement been "This prediction requires the stock price to be on or below $500.00 (US) AT the closing bell on March 31, 2008." then I would agree with you. With the current text of that statement this proposition should be closed and judged at 100%.

It's only going to matter for the time value of the money and opportunity cost in other propositions, as there's no way GOOG is going to gain 16% in less than 2 weeks. As a philosphy-of-how-this-site-is-run issue, however, it would be really nice to gain some clarification here.