"Ah, the prediction markets. The wisdom of the crowds. The polls got this one wrong, but did they, using their superior methodology, figure it out?"

Someone ought to write a FAQ on this stuff.

The wisdom of the crowds aggregates available information, which in this case, happens to be polls.

The crowds look at the polls at any given moment, decide their meaning, and pound out a value. They sum up the CW in a neat number.

If the polls are predictive, the markets are predictive. If the polls aren't predictive, the markets aren't predictive.

Petey is right, largely because so few people in Intrade are in the primary-state-du-jour they don't represent enough extra information beyond the polls and the media.

I wonder how much influence the prohibition on online gambling has effected the betting markets. It would be interesting to compare intrade v. IEM (Iowa Electronic Markets) and compare the flucation of their contract prices. Intrade is incorporated in Ireland and does not accept US payment at this point. This would seem to remove a lot of information from that market.