There have been experimental futures markets for many years now. The most famous is the one run by the University of Iowa, that has been much better than polls at predicting the outcome of the US presidential elections. This is the Economist back in 2000:

Academics at the University of Iowa set up the IEM in 1988 in order to help teach students about finance. The markets are not for futures in the classical sense—that is, promises to exchange some good or service at a fixed date and price. Rather, they are of the "cash-settled" variety. Consider the IEM’s "winner-takes-all" market for the American presidency. Each dollar invested with a central clearing-house, up to \$500 per participant, buys a bundle containing one future for every candidate. When a candidate wins, futures linked to him will pay \$1 each. As only one candidate can win, each bundle of four Bush-Gore-Nader-Buchanan futures is sure to be worth \$1. Prior to the election, investors can trade individual futures at any price for which they can find a counterparty, presumably reflecting what chance they think a candidate has of winning.

There are several factors that make it so accurate and interesting: people bet actual money on the outcome, so there's a large incentive to think about it; the decisions of investors do not affect the outcome, unlike in the stock market; and the price reflects the independent judgment of investors.

Then came The Wisdom of Crowds, James Surowiecki's excellent account of the magic of combined independent human judgment.

A classic demonstration of group intelligence is the jelly-beans-in-the-jar experiment, in which invariably the group's estimate is superior to the vast majority of the individual guesses. When finance professor Jack Treynor ran the experiment in his class with a jar that held 850 beans, the group estimate was 871. Only one of the fifty-six people in the class made a better guess.

But it turns out to be very hard to apply these ideas to practical pursuits in the corporate world. You cannot really run a futures market to figure out which of the potential investments you should pursue, because the people betting will also be deciding. You cannot do it to estimate the confidence that your organization has in meeting a schedule for the same reason.