I'm afraid this prop will pay out long for one simple reason; I think the prop was rigged.
The prop was released on August 11, the same day the media got hold of news about a Mad Cow disease screening method that would be published on August 13 in the Journal of Agriculture and Food Chemistry. Only the study wasn't first published on August 13... it was released on the web on July 12. Check out:
http://pubs.acs.org/cgi-bin/sample.cgi/jafcau/2008/56/i15/html/jf0734368.html
At the top it says "Web Release Date: July 12, 2008".
The study itself says "The present study revealed the POTENTIAL (caps mine) of fluorescent marker substances, such as lipofuscin, for the real-time detection of spinal cord on bovine carcasses and processed meat cuts including bone-in or boneless products."
Compare this to the PopSci payoff statement: "This proposition will pay out at POP$100 if scientists confirm that they've created a viable real time test for detecting beef contaminated with tissue from cow's brain or spinal cord by September 2008."
There's some surprisingly similar wording there. "Real time test" and the references to cow's brain and spinal cord indicate possible knowledge of the study's conclusions.
This should pay short because there has been no confirmation that the test is "viable" as stated in the prop, and the study itself said it only had "potential". Viablity can only be confirmed by independent follow-up studies, which have not been published to date. But in the past props have paid long on the basis of under-the-wire information that was horribly misinterpreted, like BEEBACK and HGHTEST.
I think this prop was written with advance information of this study, and PopSci sat on it too long, putting it up just ahead of publication.
But the study was published on the web a month before (something PopSci might not have known), and cannot be used as evidence that the prop has been fulfilled.
If this pays out long, we'll have to look at props a whole different way. It won't be a matter of researching and understanding. We'll have to wonder if PopSci create a prop that has already been decided on the basis of information we don't have.
And that makes this no future's exchange... it turns it into a poker game with the editors of the props.

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The 6th annual Invention Awards are here, from an inflatable tourniquet to a better lobster trap to spring-loaded hocket skates. This issue is all about the celebration of invention.
Plus: Making synthetic biology breakthroughs in a garage, building a constantly-moving ping-pong table, and a ridiculously overpowered barbecue.
So in essence, we will get paid if we invest no matter what right...? Because it's already happened.
No, it won't go that way. Either they'll pay it short because that's the way it ought to be, and never address this glaring weirdness, or they'll pay it long and never address this glaring bit of weirdness. But they won't pay both ways.