I acknowledge you are a little InTrade fanboy, and that flies OK in my book. You say there are 3,000 daily transactions on the daily DJIA prediction markets. (It was much higher than that before the CFTC fined InTrade.) While I reckon that this liquidity is enough to generate trustworthy predictions, it is very small compared to the liquidity of the financial markets or BetFair’-s liquidity. For your information, BetFair handles more transactions than the London Stock Exchange. InTrade’-s liquidity is small compared to BetFair’-s, and is certainly too small to generate profitability. That’-s what counts.