The issues do muddy the waters for using them as prediction markets. It is awesome, however for the savvy investor. My experience has been they are far, far m

The issues do muddy the waters for using them as prediction markets. It is awesome, however for the savvy investor. My experience has been they are far, far more accurate than the media. It is the nature of the accuracy that is interesting, however. They come to decisions well in advance of the media -- weeks or even months early. A good example would be this last national election cycle, the prediction markets had Rick Perry and Michelle Bachman virtually closed out while their media coverage was still treating them as viable candidates. They aren't always right in the long run, but they converge on the right answers much sooner than anything else I've seen, Nate Silver's efforts included. The biggest problem is that in the US they are either illegal (deemed to be gambling) or just too small (IEM).