Ok, I am trying to figure this out, so who will provide the feed on december 2016?... what happens if the person doesnt enter the result or enters a wrong feed?
Right now settlement is dependent upon the creator of the asset, so in that respect settlement is centralized. Eventually, price feeds similar to smartcoin price feeds will allow for a completely decentralized solution.
I do not think this is safe to use until settlement becomes decentralized. Augur and Truthcoin are developing far better systems.