Is it really a bet if there's no clearly-defined winning or losing conditions? What dates would you use to calculate the prices of the things mentioned? What "stock market", DJI? NASDAQ? FTSE? Something more exotic? Do bitcoins have to outperform "the stock market" and those commodities individually, or some kind of average?

Seems like more of a publicity stunt by someone who knows that nobody with $10k to throw around is foolish enough to agree to such ill-defined terms.